Cysteine Leukotriene Receptor Antagonist-Montelukast Effects on Diabetic Retinal Microvascular Endothelial Cells Curtail Autophagy

Purpose

Diabetic macular edema (DME) is the primary cause of vision impairment in diabetic retinopathy (DR) patients. A previous study has shown the efficacy of montelukast, a cysteinyl leukotriene receptor (CysLTR)1 antagonist, in a diabetic mouse model. This study aims to understand the CysLTR1 signaling in retinal endothelial cells and the impact of montelukast.

Methods

Primary human retinal microvascular endothelial cells (HRECs) challenged with 20 ng/mL TNF-α and 30 mM D-glucose (D-glu) for six to 24 hours served as a model of endothelial activation. HRECs were incubated with L-glucose (L-glu) as an osmotic control. CysLTR1 knockdown and montelukast pretreatment assessed CysLTR1 antagonism. Gene expression, protein expression, and cell-permeable dyes were utilized to measure autophagy and inflammation. Transendothelial electrical resistance (TER) and transendothelial migration of mononuclear leukocytes across HRECs monolayer were measured as a functional assessment of vascular permeability.

Results

Endothelial activation induced by hyperglycemia and inflammation increased CysLTR1 expression, triggering autophagy within two to six hours, IL-1β production, loss of junction integrity, decreased TER, and increased leukocyte migration within six to 24 hours. Pretreatment with montelukast effectively alleviated these effects, demonstrating its dependence on CysLTR1.

Conclusions

Dysfunctional retinal endothelium initiates a self-reinforcing loop of inflammation, autophagy, and compromised integrity associated with heightened CysLTR1 levels. The antagonistic effect of montelukast against CysLTR1 effectively mitigates these detrimental changes. This study reveals CysLTR1 as a potential therapeutic target in treating DME and offers a novel strategy to mitigate detrimental changes in DR.

Human SVIP is sufficient to stimulate tubular lysosomes and extend healthspan in well-fed Caenorhabditis elegans

Small VCP Interacting Protein (SVIP) is essential for maintaining a unique form of tubular lysosomes (TLs) in Drosophila . Although Caenorhabditis elegans do not have an annotated SVIP ortholog, expression of Drosophila SVIP in the C. elegans intestine induces TLs constitutively, increases autophagic activity, and extends healthspan. Here, we find that expression of the human ortholog of SVIP in the C. elegans gut causes similar physiological and phenotypic effects as Drosophila SVIP , albeit some effects were less pronounced. These results demonstrate that human SVIP can induce functional TLs in C. elegans but may be a weaker allele compared to Drosophila SVIP .

Early treatment with 2-deoxy-d-glucose reduces proliferative proteins in the kidney and slows cyst growth in a hypomorphic Pkd1 mouse model of autosomal dominant polycystic kidney disease (PKD)

In autosomal dominant polycystic kidney disease (ADPKD) there is cyst growth in the kidneys that leads to chronic kidney disease often requiring dialysis or kidney transplantation. There is enhanced aerobic glycolysis (Warburg effect) in the cyst lining epithelial cells that contributes to cyst growth. The glucose mimetic, 2-Deoxy-d-glucose (2-DG) inhibits glycolysis. The effect of early and late administration of 2-DG on cyst growth and kidney function was determined in Pkd1RC/RC mice, a hypomorphic PKD model orthologous to human disease. Early administration of 2-DG resulted in decreased kidney weight, cyst index, cyst number and cyst size, but no change in kidney function. 2-DG decreased proliferation. a major mediator of cyst growth, of cells lining the cyst. Late administration of 2-DG did not have an effect on cyst growth or kidney function. To determine mechanisms of decreased proliferation, an array of mTOR and autophagy proteins was measured in the kidney. 2-DG suppressed autophagic flux in Pkd1RC/RC kidneys and decreased autophagy proteins, ATG3, ATG5 and ATG12-5. 2-DG had no effect on p-mTOR or p-S6 (mTORC1) and decreased p-AMPK. 2-DG decreased p-4E-BP1, p-c-Myc and p-ERK that are known to promote proliferation and cyst growth in PKD. 2-DG decreased p-AKTS473, a marker of mTORC2. So the role of mTORC2 in cyst growth was determined. Knockout of Rictor (mTORC2) in Pkd1 knockout mice did not change the PKD phenotype. In summary, 2-DG decreases proliferation in cells lining the cyst and decreases cyst growth by decreasing proteins that are known to promote proliferation. In conclusion, the present study reinforces the therapeutic potential of 2-DG for use in patients with ADPKD.

Impact of genetic variations of gene involved in regulation of metabolism, inflammation and coagulation on pathogenesis of cardiac injuries associated with COVID-19

BACKGROUND

SARS-CoV-2 infection can result in long-term chronic cardiovascular (CV) damage after the acute phase of the illness. COVID-19 frequently causes active myocarditis, SARS-CoV-2 can directly infect and kill cardiac cells, causing severe pathology and dysfunction across the organs and cells. Till now, the pathogenesis of COVID-19-associated cardiac injuries has not been understood, but there are several factors that contribute to the progression of cardiac injuries, such as genetic, dietary, and environmental. Among them ranges of host genetic factor including metabolizing, inflammation, and coagulation related genes have a role to contribute the cardiac injuries induced by COVID-19. Hereditary DNA sequence variations contribute to the risk of illness in almost all of these diseases. Hence, we comprehended the occurrence of genetic variations of metabolizing, inflammation and coagulation-related genes in the general population, their expression in various diseases, and their impact on cardiac injuries induced by COVID-19.

METHOD

We utilized multiple databases, including PubMed (Medline), EMBASE, and Google Scholar, for literature searches.

DESCRIPTION

The genes involved in metabolism (APOE, MTHFR), coagulation (PAI-1, ACE2), and immune factors (CRP, ESR, and troponin I) may have a role in the progression of COVID-19-associated cardiac injuries. The risk factors for CVD are significantly varied between and within different regions. In healthy individuals, the ACE I allele is responsible for the predisposition to CAD, but the ACE D haplotype is responsible for susceptibility and severity, which ultimately leads to heart failure. Patients who carry the T allele of rs12329760 in the TMPRSS2 gene are at risk for developing the severe form of COVID-19. IL-6 (rs1800796/rs1800795) polymorphism is associated with an increased mortality rate and susceptibility to severe COVID-19 disease. While the putative role of IL-6 associated with chronic, inflammatory diseases like cardiac and cerebrovascular disease is well known.

CONCLUSION

The occurrence of genetic variations in the ACE-2, AGT, DPP-IV, TMPRSS2, FUIRN, IL-4, IL-6, IFN-γ, and CYP2D6 genes is varied among different populations. Examining the correlation between these variations and their protein levels and cardiac injuries induced by COVID-19 may provide valuable insights into the pathogenesis of cardiac injuries induced by COVID-19.

SIRT1 silencing promotes EMT and Crizotinib resistance by regulating autophagy through AMPK/mTOR/S6K signaling pathway in EML4-ALK L1196M and EML4-ALK G1202R mutant non-small cell lung cancer cells

Most EML4-ALK rearrangement non-small cell lung cancer (NSCLC) patients inevitably develop acquired drug resistance after treatment. The main mechanism of drug resistance is the acquired secondary mutation of ALK kinase domain. L1196M and G1202R are classical mutation sites. We urgently need to understand the underlying molecular mechanism of drug resistance to study the therapeutic targets of mutant drug-resistant NSCLC cells. The silent information regulator sirtuin1 (SIRT1) can regulate the normal energy metabolism of cells, but its role in cancer is still unclear. In our report, it was found that the SIRT1 in EML4-ALK G1202R and EML4-ALK L1196M mutant drug-resistant cells was downregulated compared with EML4-ALK NSCLC cells. The high expression of SIRT1 was related to the longer survival time of patients with lung cancer. Activation of SIRT1 induced autophagy and suppressed the invasion and migration of mutant cells. Further experiments indicated that the activation of SIRT1 inhibited the phosphorylation level of mTOR and S6K by upregulating the expression of AMPK, thus activating autophagy. SIRT1 can significantly enhanced the sensitivity of mutant cells to crizotinib, improved its ability to promote apoptosis of mutant cells, and inhibited cell proliferation. In conclusion, SIRT1 is a key regulator of drug resistant in EML4-ALK L1196M and G1202R mutant cells. SIRT1 may be a novel therapeutic target for EML4-ALK drug resistant NSCLC.

No energy, no autophagy-Mechanisms and therapeutic implications of autophagic response energy requirements

Autophagy is a lysosome-mediated self-degradation process of central importance for cellular quality control. It also provides macromolecule building blocks and substrates for energy metabolism during nutrient or energy deficiency, which are the main stimuli for autophagy induction. However, like most biological processes, autophagy itself requires ATP, and there is an energy threshold for its initiation and execution. We here present the first comprehensive review of this often-overlooked aspect of autophagy research. The studies in which ATP deficiency suppressed autophagy in vitro and in vivo were classified according to the energy pathway involved (oxidative phosphorylation or glycolysis). A mechanistic insight was provided by pinpointing the critical ATP-consuming autophagic events, including transcription/translation/interaction of autophagy-related molecules, autophagosome formation/elongation, autophagosome fusion with the lysosome, and lysosome acidification. The significance of energy-dependent fine-tuning of autophagic response for preserving the cell homeostasis, and potential implications for the therapy of cancer, autoimmunity, metabolic disorders, and neurodegeneration are discussed.

Defining standards for fluoroscopy in gastrointestinal endoscopy using Delphi methodology

Background and study aims Use of fluoroscopy in gastrointestinal endoscopy is an essential aid in advanced endoscopic interventions. However, it also raises concerns about radiation exposure. This study aimed to develop consensus-based statements for safe and effective use of fluoroscopy in gastrointestinal endoscopy, prioritizing the safety and well-being of healthcare workers and patients. Methods A modified Delphi approach was employed to achieve consensus over three rounds of surveys. Proposed statements were generated in Round 1. In the second round, panelists rated potential statements on a 5-point scale, with consensus defined as ≥80% agreement. Statements were subsequently prioritized in Round 3, using a 1 (lowest priority) to 10 (highest priority) scale. Results Forty-six experts participated, consisting of 34 therapeutic endoscopists and 12 endoscopy nurses from six continents, with an overall 45.6% female representation (n = 21). Forty-three item statements were generated in the first round. Of these, 31 statements achieved consensus after the second round. These statements were categorized into General Considerations (n = 6), Education (n = 10), Pregnancy (n = 4), Family Planning (n = 2), Patient Safety (n = 4), and Staff Safety (n = 5). In the third round, accepted statements received mean priority scores ranging from 7.28 to 9.36, with 87.2% of statements rated as very high priority (mean score ≥ 9). Conclusions This study presents consensus-based statements for safe and effective use of fluoroscopy in gastrointestinal endoscopy, addressing the well-being of healthcare workers and patients. These consensus-based statements aim to mitigate risks associated with radiation exposure while maintaining benefits of fluoroscopy, ultimately promoting a culture of safety in healthcare settings.

A mini-review-cancer energy reprogramming on drug resistance and immune response

With the growing interest to harness cancer metabolism and energy reprogramming, this mini review aimed to explain the metabolic programming revealing the mechanisms regarding the treatment resistance. This mini review summarized the prominent cancer metabolic reprogramming on macromolecules. In addition, metabolic reprogramming explaining immune response and treatment resistance as well as energy reprogramming mechanisms are briefly discussed. Finally, some prospects in MR for reversing cancer drug resistance are highlighted.

Activation of autophagy by Citri Reticulatae Semen extract ameliorates amyloid-beta-induced cell death and cognition deficits in Alzheimer's disease

JOURNAL/nrgr/04.03/01300535-202419110-00027/figure1/v/2024-03-08T184507Z/r/image-tiff Amyloid-beta-induced neuronal cell death contributes to cognitive decline in Alzheimer's disease. Citri Reticulatae Semen has diverse beneficial effects on neurodegenerative diseases, including Parkinson's and Huntington's diseases, however, the effect of Citri Reticulatae Semen on Alzheimer's disease remains unelucidated. In the current study, the anti-apoptotic and autophagic roles of Citri Reticulatae Semen extract on amyloid-beta-induced apoptosis in PC12 cells were first investigated. Citri Reticulatae Semen extract protected PC12 cells from amyloid-beta-induced apoptosis by attenuating the Bax/Bcl-2 ratio via activation of autophagy. In addition, Citri Reticulatae Semen extract was confirmed to bind amyloid-beta as revealed by biolayer interferometry in vitro, and suppress amyloid-beta-induced pathology such as paralysis, in a transgenic Caenorhabditis elegans in vivo model. Moreover, genetically defective Caenorhabditis elegans further confirmed that the neuroprotective effect of Citri Reticulatae Semen extract was autophagy-dependent. Most importantly, Citri Reticulatae Semen extract was confirmed to improve cognitive impairment, neuronal injury and amyloid-beta burden in 3×Tg Alzheimer's disease mice. As revealed by both in vitro and in vivo models, these results suggest that Citri Reticulatae Semen extract is a potential natural therapeutic agent for Alzheimer's disease via its neuroprotective autophagic effects.

The right lymphatic duct: basic anatomy and clinical relevance

The anatomical variability of the thoracic duct and the right lymphatic duct predisposes them to inadvertent damage following head and neck surgery thereby leading to chyle leak which is an uncommon complication with potentially significant associated morbidity. Although chyle leak is predominately associated with left-sided neck surgery, it also occurs as a complication of the right-sided neck dissection. Variable figures concerning chyle leakage after right-sided neck dissections were reported, ranging from 0 per cent to higher prevalences such as 14%, 24%, 33% and 60% of total cases of chyle leakages associated with neck surgery. The right-sided complications may implicate the right lymphatic duct and right-sided terminations of the thoracic duct into the venous system which occur in about 1-6% of humans. Other clinically relevant conditions involving the right-sided major lymphatic vessels include chyle leaks following right anterior cervical spine surgery, cysts of the right lymphatic duct and dilatation of the right lymphatic duct in the setting of recurrent cervical swelling. This article presents a review of the literature concerning the basic anatomy and the clinical relevance of the right lymphatic duct and the right-sided terminations of the thoracic duct into the venous circulation.

TBC1D4 antagonizes RAB2A-mediated autophagic and endocytic pathways

Macroautophagic/autophagic and endocytic pathways play essential roles in maintaining homeostasis at different levels. It remains poorly understood how both pathways are coordinated and fine-tuned for proper lysosomal degradation of diverse cargoes. We and others recently identified a Golgi-resident RAB GTPase, RAB2A, as a positive regulator that controls both autophagic and endocytic pathways. In the current study, we report that TBC1D4 (TBC1 domain family member 4), a TBC domain-containing protein that plays essential roles in glucose homeostasis, suppresses RAB2A-mediated autophagic and endocytic pathways. TBC1D4 bound to RAB2A through its N-terminal PTB2 domain, which impaired RAB2A-mediated autophagy at the early stage by preventing ULK1 complex activation. During the late stage of autophagy, TBC1D4 impeded the association of RUBCNL/PACER and RAB2A with STX17 on autophagosomes by direct interaction with RUBCNL via its N-terminal PTB1 domain. Disruption of the autophagosomal trimeric complex containing RAB2A, RUBCNL and STX17 resulted in defective HOPS recruitment and eventually abortive autophagosome-lysosome fusion. Furthermore, TBC1D4 inhibited RAB2A-mediated endocytic degradation independent of RUBCNL. Therefore, TBC1D4 and RAB2A form a dual molecular switch to modulate autophagic and endocytic pathways. Importantly, hepatocyte- or adipocyte-specific tbc1d4 knockout in mice led to elevated autophagic flux and endocytic degradation and tissue damage. Together, this work establishes TBC1D4 as a critical molecular brake in autophagic and endocytic pathways, providing further mechanistic insights into how these pathways are intertwined both in vitro and in vivo.Abbreviations: ACTB: actin beta; ATG9: autophagy related 9; ATG14: autophagy related 14; ATG16L1: autophagy related 16 like 1; CLEM: correlative light electron microscopy; Ctrl: control; DMSO: dimethyl sulfoxide; EGF: epidermal growth factor; EGFR: epidermal growth factor receptor; FL: full length; GAP: GTPase-activating protein; GFP: green fluorescent protein; HOPS: homotypic fusion and protein sorting; IP: immunoprecipitation; KD: knockdown; KO: knockout; LAMP1: lysosomal associated membrane protein 1; MAP1LC3B/LC3B: microtubule associated protein 1 light chain 3 beta; OE: overexpression; PG: phagophore; PtdIns3K: class III phosphatidylinositol 3-kinase; SLC2A4/GLUT4: solute carrier family 2 member 4; SQSTM1/p62: sequestosome 1; RUBCNL/PACER: rubicon like autophagy enhancer; STX17: syntaxin 17; TAP: tandem affinity purification; TBA: total bile acid; TBC1D4: TBC1 domain family member 4; TUBA1B: tubulin alpha 1b; ULK1: unc-51 like autophagy activating kinase 1; VPS39: VPS39 subunit of HOPS complex; WB: western blot; WT: wild type.

PPM1G promotes autophagy and progression of pancreatic cancer via upregulating HMGB1

Pancreatic cancer remains one of the most aggressive and lethal malignancies worldwide, with a dismal 5-year relative survival rates of only 12%. Therefore, it is urgent to discover the key molecular markers to improve the therapeutic outcomes in pancreatic cancer. Herein, we first demonstrated that PPM1G is upregulated in pancreatic cancer and that PPM1G depletion decreases pancreatic cancer cell growth in vitro and in vivo. High PPM1G expression was linked to short overall survival of pancreatic cancer patients, which was further validated in the TCGA database. Moreover, by detecting Beclin 1, LC3-II, and SQSTM1/p62 expressions and observing autolysosome under transmission electron microscope, we discovered that PPM1G is a novel positive regulator of macroautophagy/autophagy. Furthermore, by using immunoprecipitation-mass spectrometry (IP-MS) analysis and following systemic molecular biology experiment, we demonstrated PPM1G promotes the autophagy and proliferation of pancreatic cancer by directly upregulating HMGB1. Additionally, patients with both high PPM1G and high HMGB1 exhibited poorer prognosis in our cohort. This study preliminarily investigated the possibility of PPM1G as a potential therapeutic target and prognostic biomarker in pancreatic cancer patients.

Big1 is a newly identified autophagy regulator that is critical for a fully functional V-ATPase

The vacuolar-type H+-translocating ATPase (V-ATPase) is the major proton pump for intraorganellar acidification. Therefore, the integrity of the V-ATPase is closely associated with cellular homeostasis, and mutations in genes encoding V-ATPase components and assembly factors have been reported in certain types of diseases. For instance, the recurrent mutations of ATP6AP1, a gene encoding a V-ATPase accessory protein, have been associated with cancers and immunodeficiency. With the aim of studying V-ATPase-related mutations using the yeast model system, we report that Big1 is another homologue of ATP6AP1 in yeast cells, and we characterize the role of Big1 in maintaining a fully functional V-ATPase. In addition to its role in acidifying the vacuole or lysosome, our data support the concept that the V-ATPase may function as part of a signaling pathway to regulate macroautophagy/autophagy through a mechanism that is independent from Tor/MTOR.

Let's talk about flux: the rising potential of autophagy rate measurements in disease

Macroautophagy/autophagy is increasingly implicated in a variety of diseases, making it an attractive therapeutic target. However, many aspects of autophagy are not fully understood and its impact on many diseases remains debatable and context-specific. The lack of systematic and dynamic measurements in these cases is a key reason for this ambiguity. In recent years, Loos et al. 2014 and Beesabathuni et al. 2022 developed methods to quantitatively measure autophagy holistically. In this commentary, we pose some of the unresolved biological questions regarding autophagy and consider how quantitative measurements may address them. While the applications are ever-expanding, we provide specific use cases in cancer, virus infection, and mechanistic screening. We address how the rate measurements themselves are central to developing cancer therapies and present ways in which these tools can be leveraged to dissect the complexities of virus-autophagy interactions. Screening methods can be combined with rate measurements to mechanistically decipher the labyrinth of autophagy regulation in cancer and virus infection. Taken together, these approaches have the potential to illuminate the underlying mechanisms of various diseases.Abbreviation MAP1LC3/LC3: microtubule-associated protein 1 light chain 3; R1: rate of autophagosome formation; R2: rate of autophagosome-lysosome fusion; R3: rate of autolysosome turnover.

Non-autophagic Golgi-LC3 lipidation facilitates TFE3 stress response against Golgi dysfunction

Lipidated ATG8/LC3 proteins are recruited to single membrane compartments as well as autophagosomes, supporting their functions. Although recent studies have shown that Golgi-LC3 lipidation follows Golgi damage, its molecular mechanism and function under Golgi stress remain unknown. Here, by combining DLK1 overexpression as a new strategy for induction of Golgi-specific LC3 lipidation, and the application of Golgi-damaging reagents, we unravel the mechanism and role of Golgi-LC3 lipidation. Upon DLK1 overexpression, LC3 is lipidated on the Golgi apparatus in an ATG12-ATG5-ATG16L1 complex-dependent manner; a post-Golgi trafficking blockade is the primary cause of this lipidation. During Golgi stress, ATG16L1 is recruited through its interaction with V-ATPase for Golgi-LC3 lipidation. After post-Golgi trafficking inhibition, TFE3, a key regulator of the Golgi stress response, is translocated to the nucleus. Defects in LC3 lipidation disrupt this translocation, leading to an attenuation of the Golgi stress response. Together, our results reveal the mechanism and unexplored function of Golgi-LC3 lipidation in the Golgi stress response.

Synergistic effects of resveratrol and enzyme replacement therapy in the Mucopolysaccharidosis type I

Mucopolysaccharidosis type I (MPS I) is a rare genetic disorder caused by mutations in the IDUA gene, leading to alpha-L-iduronidase enzyme deficiency and resulting in the accumulation of glycosaminoglycans (GAG; heparan and dermatan sulfate) in lysosomes. The consequent GAG accumulation within cells leads to organ dysfunction and a range of debilitating symptoms. Enzyme replacement therapy (ERT) is the prevailing treatment, but its limitations (including high cost, time requirements, inefficiency in treatment of central nervous system (CNS), and immunogenicity) necessitate exploration of alternative therapeutic strategies. This research propose a novel approach leveraging the synergistic effects of ERT and resveratrol-induced autophagy. Resveratrol, with its immunomodulatory and GAG degradation-stimulating properties, holds a promise in mitigating immune responses triggered by ERT. Moreover, its ability to penetrate the blood-brain barrier presents a potential solution for addressing CNS manifestations. This study employed cells from MPS I patients to investigate the combined effects of resveratrol and the enzyme. Evaluation of the therapeutic impact involved assessing GAG accumulation, enzyme testing, and examining lysosome functionality and the autophagy process through fluorescence microscopy and Western blotting. The combined therapy stimulated the lysosomal mannose-6-phosphate receptor (M6PR) and lysosome biogenesis through the transcription factor EB (TFEB). Additionally, initial block of autophagy in autophagosome formation was relieved after the combined therapy and resveratrol alone. Together with increased enzyme activity through stimulation of the receptor, this synergistic therapy can be considered a new potential treatment for MPS I patients, improving their overall quality of life.

β-carotene protects against α-amanitin nephrotoxicity via modulation of oxidative, autophagic, nitric oxide signaling, and polyol pathways in rat kidneys

Alpha-amanitin (α-AMA), a toxic component of Amanita phalloides, causes severe hepato- and nephrotoxicity. This study investigated the protective effects of βeta-carotene (βC) against α-AMA-induced kidney damage in rats. Thirty-two male Sprague-Dawley rats were divided into four groups: Control, βC (50 mg/kg/day), α-AMA (3 mg/kg), and βC+α-AMA. βC was administered orally for 7 days before α-AMA injection. Renal function, oxidative stress markers, histopathological changes, and enzyme activities were evaluated 48 h post-α-AMA administration. α-AMA significantly increased serum creatinine and urea levels, decreased glutathione and catalase activity, and increased malondialdehyde levels (P < 0.001). βC pretreatment attenuated these changes (P < 0.05). Histopathological examination revealed reduced tubular degeneration in the βC+α-AMA group (P < 0.001). Immunohistochemical analysis showed increased LC3B and Beclin-1 expression in α-AMA-treated rats, indicating enhanced autophagy, partially reversed by βC. Additionally, α-AMA reduced nitric oxide synthase (NOS) activity and increased aldose reductase (AR) activity, both normalized by βC pretreatment (P < 0.01). βC demonstrates protective effects against α-AMA-induced nephrotoxicity through antioxidant action, modulation of autophagy, and regulation of NOS and AR pathways, suggesting its potential as a therapeutic agent in α-AMA poisoning.

Macroautophagy/autophagy promotes resistance to KRASG12D-targeted therapy through glutathione synthesis

KRASG12D mutation-driven pancreatic ductal adenocarcinoma (PDAC) represents a major challenge in medicine due to late diagnosis and treatment resistance. Here, we report that macroautophagy (hereafter autophagy), a cellular degradation and recycling process, contributes to acquired resistance against novel KRASG12D-targeted therapy. The KRASG12D protein inhibitor MRTX1133 induces autophagy in KRASG12D-mutated PDAC cells by blocking MTOR activity, and increased autophagic flux prevents apoptosis. Mechanistically, autophagy facilitates the generation of glutamic acid, cysteine, and glycine for glutathione synthesis. Increased glutathione levels reduce reactive oxygen species production, which impedes CYCS translocation from mitochondria to the cytosol, ultimately preventing the formation of the APAF1 apoptosome. Consequently, genetic interventions (utilizing ATG5 or BECN1 knockout) or pharmacological inhibition of autophagy (with chloroquine, bafilomycin A1, or spautin-1) enhance the anticancer activity of MRTX1133 in vitro and in various animal models (subcutaneous, patient-derived xenograft, and orthotopic). Moreover, the release of histones by apoptotic cells triggers an adaptive immune response when combining an autophagy inhibitor with MRTX1133 in immunocompetent mice. These findings establish a new strategy to overcome KRASG12D-targeted therapy resistance by inhibiting autophagy-dependent glutathione synthesis.

Molecular signaling and clinical implications in the human aging-cancer cycle

It is well documented that aging is associated with cancer, and likewise, cancer survivors display accelerated aging. As the number of aging individuals and cancer survivors continues to grow, it raises additional concerns across society. Therefore, unraveling the molecular mechanisms of aging in tissues is essential to developing effective therapies to fight the aging and cancer diseases in cancer survivors and cancer patients. Indeed, cellular senescence is a critical response, or a natural barrier to suppress the transition of normal cells into cancer cells, however, hypoxia which is physiologically required to maintain the stem cell niche, is increased by aging and inhibits senescence in tissues. Interestingly, oxygen restriction or hypoxia increases longevity and slows the aging process in humans, but hypoxia can also drive angiogenesis to facilitate cancer progression. In addition, cancer treatment is considered as one of the major reasons that drive cellular senescence, subsequently followed by accelerated aging. Several clinical trials have recently evaluated inhibitors to eliminate senescent cells. However, some mechanisms of aging typically can also retard cancer cell growth and progression, which might require careful strategy for better clinical outcomes. Here we describe the molecular regulation of aging and cancer in crosstalk with DNA damage and hypoxia signaling pathways in cancer patients and cancer survivors. We also update several therapeutic strategies that might be critical in reversing the cancer treatment-associated aging process.

CYP14 family in Caenorhabditis elegans: Mitochondrial function, detoxification, and lifespan

CYP-14 members of the Caenorhabditis elegans (C. elegans) Cytochrome P450 (CYP) enzyme family, plays important roles in mitochondrial dysfunction, detoxification, lipid metabolism, defense and lifespan regulation. The review identifies CYP-14 members: cyp-14A1, cyp-14A2, cyp-14A3, cyp-14A4, cyp-14A5 and their homology with human CYP families. Despite limited studies on C. elegans cyp-14 members, the findings unraveled their complex crosstalk between mitochondrial stress, detoxification mechanisms, and lifespan regulation, emphasizing the complexity of these interconnected pathways as well as how their regulation depends on environmental cues changes including pH, nutrients, ROS and chemical stressors. The review underscores the translational relevance to human health, shedding light on potential human homologues and their implications in age-related, metabolic and respiratory diseases. Among other genes, cyp-14A2 and cyp-14A4 predominate the mitochondrial function, heat resistance, lipid metabolism, detoxification and lifespan pathways. In conclusion, these insights pave the way for future research, offering promising avenues for therapeutic interventions targeting CYP-14 activity to address age-related diseases and promote healthy aging.

Genetic deletion of calcium-independent phospholipase A2γ protects mice from diabetic nephropathy

Calcium-independent phospholipase A2γ (iPLA2γ) is localized in glomerular epithelial cells (GECs)/podocytes at the mitochondria and endoplasmic reticulum, and can mediate release of arachidonic acid and prostanoids. Global knockout (KO) of iPLA2γ in mice did not cause albuminuria, but resulted in mitochondrial structural abnormalities and enhanced autophagy in podocytes. In acute glomerulonephritis, deletion of iPLA2γ exacerbated albuminuria and podocyte injury. This study addresses the role of iPLA2γ in diabetic nephropathy. Hyperglycemia was induced in male mice with streptozotocin (STZ). STZ induced progressive albuminuria in control mice (over 21 weeks), while albuminuria did not increase in iPLA2γ KO mice, remaining comparable to untreated groups. Despite similar exposure to STZ, the STZ-treated iPLA2γ KO mice developed a lower level of hyperglycemia compared to STZ-treated control. However, there was no significant correlation between the degree of hyperglycemia and albuminuria, and even iPLA2γ KO mice with greatest hyperglycemia did not develop significant albuminuria. Mortality at 21 weeks was greatest in diabetic control mice. Sclerotic glomeruli and enlarged glomerular capillary loops were increased significantly in diabetic control compared to diabetic iPLA2γ KO mice. Glomerular matrix was expanded in diabetic mice, with control exceeding iPLA2γ KO. Glomerular autophagy (increased LC3-II and decreased p62) was enhanced in diabetic iPLA2γ KO mice compared to control. Treatment of cultured GECs with H2O2 resulted in increased cell death in control GECs compared to iPLA2γ KO, and the increase was slightly greater in medium with high glucose compared to low glucose. H2O2-induced cell death was not affected by inhibition of prostanoid production with indomethacin. In conclusion, mice with global deletion of iPLA2γ are protected from developing chronic glomerular injury in diabetic nephropathy. This is associated with increased glomerular autophagy.

Synergistic Combination of Quercetin and Mafosfamide in Treatment of Bladder Cancer Cells

Bladder cancer, which has a rising incidence, is the 10th most common cancer. The transitional cell carcinoma histotype is aggressive and often current therapies are ineffective. We investigated the anti-proliferative effect of quercetin, a natural flavonoid, in combination with the alkylating agent mafosfamide (MFA) on two human bladder cancer cell lines, namely RT112 and J82, representing the progression from low-grade to high-grade tumors, respectively. In both cell types, the combined treatment led to a synergic reduction in cell viability confirmed by a combination index of less than one, though different biological responses were noted. In J82 cells, MFA alone and, to a lesser extent, with quercetin caused cell cycle arrest in the G2/M phase, but only the combined treatment triggered apoptotic cell death. In contrast, in RT112 cells, quercetin induced autophagy, evidenced by the autophagosome formation and the increase in LC-3 lipidation. Interestingly, the synergistic effect was observed only when cells were pre-treated with MFA for 24 h before adding quercetin, not in the reverse order. This suggests that quercetin may help overcome MFA resistance to apoptosis. Although further studies are needed, investigating the combined effects of quercetin and MFA could help elucidate the mechanisms of drug resistance in bladder cancer treatment.

Parkinson's disease models and death signaling: what do we know until now?

Parkinson's disease (PD) is the second neurodegenerative disorder most prevalent in the world, characterized by the loss of dopaminergic neurons in the Substantia Nigra (SN). It is well known for its motor and non-motor symptoms including bradykinesia, resting tremor, psychiatric, cardiorespiratory, and other dysfunctions. Pathological apoptosis contributes to a wide variety of diseases including PD. Various insults and/or cellular phenotypes have been shown to trigger distinct signaling events leading to cell death in neurons affected by PD. The intrinsic or mitochondrial pathway, inflammatory or oxidative stress-induced extrinsic pathways are the main events associated with apoptosis in PD-related neuronal loss. Although SN is the main brain area studied so far, other brain nuclei are also affected by the disease leading to non-classical motor symptoms as well as non-motor symptoms. Among these, the respiratory symptoms are often overlooked, yet they can cause discomfort and may contribute to patients shortened lifespan after disease diagnosis. While animal and in vitro models are frequently used to investigate the mechanisms involved in the pathogenesis of PD in both the SN and other brain regions, these models provide only a limited understanding of the disease's actual progression. This review offers a comprehensive overview of some of the most studied forms of cell death, including recent research on potential treatment targets for these pathways. It highlights key findings and milestones in the field, shedding light on the potential role of understanding cell death in the prevention and treatment of the PD. Therefore, unraveling the connection between these pathways and the notable pathological mechanisms observed during PD progression could enhance our comprehension of the disease's origin and provide valuable insights into potential molecular targets for the developing therapeutic interventions.

A mitochondrial redox switch licenses the onset of morphogenesis in animals

Embryos undergo pre-gastrulation cleavage cycles to generate a critical cell mass before transitioning to morphogenesis. The molecular underpinnings of this transition have traditionally centered on zygotic chromatin remodeling and genome activation1,2, as their repression can prevent downstream processes of differentiation and organogenesis. Despite precedents that oxygen depletion can similarly suspend development in early embryos3-6, hinting at a pivotal role for oxygen metabolism in this transition, whether there is a bona fide chemical switch that licenses the onset of morphogenesis remains unknown. Here we discover that a mitochondrial oxidant acts as a metabolic switch to license the onset of animal morphogenesis. Concomitant with the instatement of mitochondrial membrane potential, we found a burst-like accumulation of mitochondrial superoxide (O2 -) during fly blastoderm formation. In vivo chemistry experiments revealed that an electron leak from site IIIQo at ETC Complex III is responsible for O2 - production. Importantly, depleting mitochondrial O2 - fully mimics anoxic conditions and, like anoxia, induces suspended animation prior to morphogenesis, but not after. Specifically, H2O2, and not ONOO-, NO, or HO•, can single-handedly account for this mtROS-based response. We demonstrate that depleting mitochondrial O2 - similarly prevents the onset of morphogenetic events in vertebrate embryos and ichthyosporea, close relatives of animals. We postulate that such redox-based metabolic licensing of morphogenesis is an ancient trait of holozoans that couples the availability of oxygen to development, conserved from early-diverging animal relatives to vertebrates.

Suppression of hepatic steatosis in non-alcoholic steatohepatitis model by modified Xiaoyao San formula: Evidence, mechanisms and perspective

In this letter, we comment on a recent publication by Mei et al, in the World Journal of Hepatology, investigating the hepatoprotective effects of the modified Xiaoyao San (MXS) formula in a male rat model of non-alcoholic steatohepatitis (NASH). The authors found that MXS treatment mitigated hepatic steatosis and inflammation in the NASH model, as evidenced by the reduction in lipid droplets (LDs), fibrosis markers and lipogenic factors. Interestingly, these hepatoprotective effects were associated with androgen upregulation (based on metabolomics analysis of male steroid hormone metabolites), adenosine 5’-monophosphate-activated protein kinase (AMPK) activation, and restoration of phosphatase and tensin homolog (PTEN) expression. However, the authors did not clearly discuss the relationships between MXS-induced hepatic steatosis reduction in the NASH model, and androgen upregulation, AMPK activation, and restoration of PTEN expression. This editorial emphasizes the reported mechanisms and explains how they act or interact with each other to reduce hepatic steatosis and inflammation in the NASH model. As a perspective, we propose additional mechanisms (such as autophagy/lipophagy activation in hepatocytes) for the clearance of LDs and suppression of hepatic steatosis by MXS in the NASH model. A proper understanding of the mechanisms of MXS-induced reduction of hepatic steatosis might help in the treatment of NASH and related diseases.

Suppression of hepatic steatosis in non-alcoholic steatohepatitis model by modified Xiaoyao San formula: Evidence, mechanisms and perspective

In this letter, we comment on a recent publication by Mei et al, in the World Journal of Hepatology, investigating the hepatoprotective effects of the modified Xiaoyao San (MXS) formula in a male rat model of non-alcoholic steatohepatitis (NASH). The authors found that MXS treatment mitigated hepatic steatosis and inflammation in the NASH model, as evidenced by the reduction in lipid droplets (LDs), fibrosis markers and lipogenic factors. Interestingly, these hepatoprotective effects were associated with androgen upregulation (based on metabolomics analysis of male steroid hormone metabolites), adenosine 5'-monophosphate-activated protein kinase (AMPK) activation, and restoration of phosphatase and tensin homolog (PTEN) expression. However, the authors did not clearly discuss the relationships between MXS-induced hepatic steatosis reduction in the NASH model, and androgen upregulation, AMPK activation, and restoration of PTEN expression. This editorial emphasizes the reported mechanisms and explains how they act or interact with each other to reduce hepatic steatosis and inflammation in the NASH model. As a perspective, we propose additional mechanisms (such as autophagy/lipophagy activation in hepatocytes) for the clearance of LDs and suppression of hepatic steatosis by MXS in the NASH model. A proper understanding of the mechanisms of MXS-induced reduction of hepatic steatosis might help in the treatment of NASH and related diseases.

NFE2L2 and ferroptosis resistance in cancer therapy

NFE2-like basic leucine zipper transcription factor 2 (NFE2L2, also known as NRF2), is a key transcription factor in the cellular defense against oxidative stress, playing a crucial role in cancer cell survival and resistance to therapies. This review outlines the current knowledge on the link between NFE2L2 and ferroptosis - a form of regulated cell death characterized by iron-dependent lipid peroxidation - within cancer cells. While NFE2L2 activation can protect normal cells from oxidative damage, its overexpression in cancer cells contributes to drug resistance by upregulating antioxidant defenses and inhibiting ferroptosis. We delve into the molecular pathways of ferroptosis, highlighting the involvement of NFE2L2 and its target genes, such as NQO1, HMOX1, FTH1, FTL, HERC2, SLC40A1, ABCB6, FECH, PIR, MT1G, SLC7A11, GCL, GSS, GSR, GPX4, AIFM2, MGST1, ALDH1A1, ALDH3A1, and G6PD, in ferroptosis resistance. Understanding the delicate balance between NFE2L2's protective and deleterious roles could pave the way for novel therapeutic strategies targeting NFE2L2 to enhance the efficacy of ferroptosis inducers in cancer therapy.

Autophagy and autophagic cell death in sepsis: friend or foe?

In sepsis, inflammation, and nutrient deficiencies endanger cellular homeostasis and survival. Autophagy is primarily a mechanism of cellular survival under fasting conditions. However, autophagy-dependent cell death, known as autophagic cell death, is proinflammatory and can exacerbate sepsis. Autophagy also regulates various types of non-inflammatory and inflammatory cell deaths. Non-inflammatory apoptosis tends to suppress inflammation, however, inflammatory necroptosis, pyroptosis, ferroptosis, and autophagic cell death lead to the release of inflammatory cytokines and damage-associated molecular patterns (DAMPs) and amplify inflammation. The selection of cell death mechanisms is complex and often involves a mixture of various styles. Similarly, protective autophagy and lethal autophagy may be triggered simultaneously in cells. How cells balance the regulatory mechanisms of these processes is an area of interest that is still under investigation. Therapies aimed at modulating autophagy are considered promising. Enhancing autophagy helps clear and recycle damaged organelles and reduce the burden of inflammatory processes while inhibiting excessive autophagy, which could prevent autophagic cell death. In this review, we introduce recent advances in research and the complex regulatory system of autophagy in sepsis.

Ellagic Acid Reduces Cadmium Exposure-Induced Apoptosis in HT22 Cells via Inhibiting Oxidative Stress and Mitochondrial Dysfunction and Activating Nrf2/HO-1 Pathway

Exposure to cadmium sulfate (CdSO4) can lead to neurotoxicity. Nevertheless, the precise molecular mechanisms underlying this phenomenon remain unclear, and effective treatment strategies are scarce. This study explored the protective effects of ellagic acid (EA), a natural polyphenolic compound, against CdSO4 exposure-induced neurotoxicity in HT22 cells and the underlying molecular mechanisms. Our findings demonstrated that exposure of HT22 cells to CdSO4 resulted in apoptosis, which was effectively reversed by EA in a dose-dependent manner. EA supplementation also decreased reactive oxygen species (ROS) and mitochondrial ROS production, reduced malondialdehyde (MDA) levels, and restored the activities of superoxide dismutase (SOD) and catalase (CAT). Additionally, EA supplementation at 5-20 μM significantly counteracted Cd-induced the loss of mitochondrial membrane potential and the decrease of ATP and reduced the ratio of Bax/Bcl-2 and cleaved-caspase-3 protein expression. Furthermore, EA supplementation resulted in the upregulation of Nrf2 and HO-1 protein and mRNAs while simultaneously downregulating the phosphorylation of JNK and p38 proteins. The pharmacological inhibition of c-Jun N-terminal kinase (JNK) partially attenuated the activation of the Nrf2/HO-1 pathway induced by CdSO4 and exacerbated its cytotoxic effects. In conclusion, our findings suggest that ethyl acetate (EA) supplementation offers protective effects against CdSO4-induced apoptosis in HT22 cells by inhibiting oxidative stress and activating the Nrf2 signaling pathway. Furthermore, the activation of the JNK pathway appears to play a protective role in CdSO4-induced apoptosis in HT22 cells.

Inhibitory effects of extracts from Eucalyptus gunnii on α-synuclein amyloid fibrils

Amyloid fibril formation is associated with various amyloidoses, including neurodegenerative diseases such as Alzheimer's and Parkinson's diseases. Despite the numerous studies on the inhibition of amyloid formation, the prevention and treatment of a majority of amyloid-related disorders are still challenging. In this study, we investigated the effects of various plant extracts on amyloid formation of α-synuclein. We found that the extracts from Eucalyptus gunnii are able to inhibit amyloid formation, and to disaggregate preformed fibrils, in vitro. The extract itself did not lead to cell damage. In the extract, miquelianin, which is a glycosylated form of quercetin and has been detected in the plasma and the brain, was identified and assessed to have a moderate inhibitory activity, compared to the effects of ellagic acid and quercetin, which are strong inhibitors for amyloid formation. The properties of miquelianin provide insights into the mechanisms controlling the assembly of α-synuclein in the brain.

Lysosomal Ca2+ release-facilitated TFEB nuclear translocation alleviates ischemic brain injury by attenuating autophagic/lysosomal dysfunction in neurons

Neuronal death was frequently driven by autophagic/lysosomal dysfunction after ischemic stroke, whereas how to restore the impaired autophagic flux remained elusive. Autophagic/lysosomal signaling could be augmented after transcription factor EB (TFEB) nuclear translocation, which was facilitated by its dephosphorylation. A key TFEB dephosphorylase was calcineurin (CaN), whose activity was drastically regulated by cytosolic calcium ion concentration ([Ca2+]) controlled by lysosomal Ca2+ channel-like protein of TRPML1. Our research shows that ML-SA1, an agonist of the TRPML1 channel, significantly enhanced the lysosomal Ca2+ release and the CaN expression in penumbric neurons, subsequently promoted TFEB nuclear translocation, and greatly reversed autophagy/lysosome dysfunction. Moreover, ML-SA1 treatment significantly reduced neuronal loss, infarct size, and neurological deficits. By contrast, ML-SI3, an inhibitor of TRPML1, inhibited the lysosomal Ca2+ release conversely, aggravated the impairment of autophagic flux and consequentially exacerbated brain stroke lesion. These studies suggest that TRPML1 elevation alleviates ischemic brain injury by restoring autophagic/lysosomal dysfunction via Lysosomal Ca2+ release-facilitated TFEB nuclear translocation in neurons.

Universal high-throughput image quantification of subcellular structure dynamics and spatial distributions within cells

Image analysis of subcellular structures and biological processes relies on specific, context-dependent pipelines, which are labor-intensive, constrained by the intricacies of the specific biological system, and inaccessible to broader applications. Here we introduce the application of dispersion indices, a statistical tool traditionally employed by economists, to analyze the spatial distribution and heterogeneity of subcellular structures. This computationally efficient high-throughput approach, termed GRID (Generalized Readout of Image Dispersion), is highly generalizable, compatible with open-source image analysis software, and adaptable to diverse biological scenarios. GRID readily quantifies diverse structures and processes to include autophagic puncta, mitochondrial clustering, and microtubule dynamics. Further, GRID is versatile, applicable to both 2D cell cultures and 3D multicellular organoids, and suitable for high-throughput screening and performance metric measurements, such as half-maximal effective concentration (EC50) values. The approach enables mechanistic analysis of critical subcellular structure processes of relevance for diseases ranging from metabolic and neuronal diseases to cancer as well as a first-pass screening method for identifying biologically active agents for drug discovery.

Identification of KW-2449 as a dual inhibitor of ferroptosis and necroptosis reveals that autophagy is a targetable pathway for necroptosis inhibitors to prevent ferroptosis

Necroptosis and ferroptosis are two distinct forms of necrotic-like cell death in terms of their morphological features and regulatory mechanisms. These two types of cell death can coexist in disease and contribute to pathological processes. Inhibition of both necroptosis and ferroptosis has been shown to enhance therapeutic effects in treating complex necrosis-related diseases. However, targeting both necroptosis and ferroptosis by a single compound can be challenging, as these two forms of cell death involve distinct molecular pathways. In this study, we discovered that KW-2449, a previously described necroptosis inhibitor, also prevented ferroptosis both in vitro and in vivo. Mechanistically, KW-2449 inhibited ferroptosis by targeting the autophagy pathway. We further identified that KW-2449 functioned as a ULK1 (Unc-51-like kinase 1) inhibitor to block ULK1 kinase activity in autophagy. Remarkably, we found that Necrostatin-1, a classic necroptosis inhibitor that has been shown to prevent ferroptosis, also targets the autophagy pathway to suppress ferroptosis. This study provides the first understanding of how necroptosis inhibitors can prevent ferroptosis and suggests that autophagy is a targetable pathway for necroptosis inhibitors to prevent ferroptosis. Therefore, the identification and design of pharmaceutical molecules that target the autophagy pathway from necroptosis inhibitors is a promising strategy to develop dual inhibitors of necroptosis and ferroptosis in clinical application.

Acquisition of neurodegenerative features in isogenic OPTN(E50K) human stem cell-derived retinal ganglion cells associated with autophagy disruption and mTORC1 signaling reduction

The ability to derive retinal ganglion cells (RGCs) from human pluripotent stem cells (hPSCs) has led to numerous advances in the field of retinal research, with great potential for the use of hPSC-derived RGCs for studies of human retinal development, in vitro disease modeling, drug discovery, as well as their potential use for cell replacement therapeutics. Of all these possibilities, the use of hPSC-derived RGCs as a human-relevant platform for in vitro disease modeling has received the greatest attention, due to the translational relevance as well as the immediacy with which results may be obtained compared to more complex applications like cell replacement. While several studies to date have focused upon the use of hPSC-derived RGCs with genetic variants associated with glaucoma or other optic neuropathies, many of these have largely described cellular phenotypes with only limited advancement into exploring dysfunctional cellular pathways as a consequence of the disease-associated gene variants. Thus, to further advance this field of research, in the current study we leveraged an isogenic hPSC model with a glaucoma-associated mutation in the Optineurin (OPTN) protein, which plays a prominent role in autophagy. We identified an impairment of autophagic-lysosomal degradation and decreased mTORC1 signaling via activation of the stress sensor AMPK, along with subsequent neurodegeneration in OPTN(E50K) RGCs differentiated from hPSCs, and have further validated some of these findings in a mouse model of ocular hypertension. Pharmacological inhibition of mTORC1 in hPSC-derived RGCs recapitulated disease-related neurodegenerative phenotypes in otherwise healthy RGCs, while the mTOR-independent induction of autophagy reduced protein accumulation and restored neurite outgrowth in diseased OPTN(E50K) RGCs. Taken together, these results highlighted that autophagy disruption resulted in increased autophagic demand which was associated with downregulated signaling through mTORC1, contributing to the degeneration of RGCs.

Methylarginine targeting chimeras for lysosomal degradation of intracellular proteins

A paradigm shift in drug development is the discovery of small molecules that harness the ubiquitin-proteasomal pathway to eliminate pathogenic proteins. Here we provide a modality for targeted protein degradation in lysosomes. We exploit an endogenous lysosomal pathway whereby protein arginine methyltransferases (PRMTs) initiate substrate degradation via arginine methylation. We developed a heterobifunctional small molecule, methylarginine targeting chimera (MrTAC), that recruits PRMT1 to a target protein for induced degradation in lysosomes. MrTAC compounds degraded substrates across cell lines, timescales and doses. MrTAC degradation required target protein methylation for subsequent lysosomal delivery via microautophagy. A library of MrTAC molecules exemplified the generality of MrTAC to degrade known targets and neo-substrates-glycogen synthase kinase 3β, MYC, bromodomain-containing protein 4 and histone deacetylase 6. MrTAC selectively degraded target proteins and drove biological loss-of-function phenotypes in survival, transcription and proliferation. Collectively, MrTAC demonstrates the utility of endogenous lysosomal proteolysis in the generation of a new class of small molecule degraders.

White matter hyperintensity genetic risk factor TRIM47 regulates autophagy in brain endothelial cells

White matter hyperintensity (WMH) is strongly correlated with age-related dementia and hypertension, but its pathogenesis remains obscure. Genome-wide association studies identified TRIM47 at the 17q25 locus as a top genetic risk factor for WMH formation. TRIM family is a class of E3 ubiquitin ligase with pivotal functions in autophagy, which is critical for brain endothelial cell (ECs) remodeling during hypertension. We hypothesize that TRIM47 regulates autophagy and its loss-of-function disturbs cerebrovasculature. Based on transcriptomics and immunohistochemistry, TRIM47 is found highly expressed by brain ECs in human and mouse, and its transcription is upregulated by artificially induced autophagy while downregulated in hypertension-like conditions. Using in silico simulation, immunocytochemistry and super-resolution microscopy, we predicted a highly conserved binding site between TRIM47 and the LIR (LC3-interacting region) motif of LC3B. Importantly, pharmacological autophagy induction increased Trim47 expression on mouse ECs (b.End3) culture, while silencing Trim47 significantly increased autophagy with ULK1 phosphorylation induction, transcription, and vacuole formation. Together, we demonstrate that TRIM47 is an endogenous inhibitor of autophagy in brain ECs, and such TRIM47-mediated regulation connects genetic and physiological risk factors for WMH formation but warrants further investigation.

Advances in natural products modulating autophagy influenced by cellular stress conditions and their anticancer roles in the treatment of ovarian cancer

Autophagy is a conservative catabolic process that typically serves a cell-protective function. Under stress conditions, when the cellular environment becomes unstable, autophagy is activated as an adaptive response for self-protection. Autophagy delivers damaged cellular components to lysosomes for degradation and recycling, thereby providing essential nutrients for cell survival. However, this function of promoting cell survival under stress conditions often leads to malignant progression and chemotherapy resistance in cancer. Consequently, autophagy is considered a potential target for cancer therapy. Herein, we aim to review how natural products act as key modulators of autophagy by regulating cellular stress conditions. We revisit various stressors, including starvation, hypoxia, endoplasmic reticulum stress, and oxidative stress, and their regulatory relationship with autophagy, focusing on recent advances in ovarian cancer research. Additionally, we explore how polyphenolic compounds, flavonoids, alkaloids, terpenoids, and other natural products modulate autophagy mediated by stress responses, affecting the malignant biological behavior of cancer. Furthermore, we discuss their roles in ovarian cancer therapy. This review emphasizes the importance of natural products as valuable resources in cancer therapeutics, highlighting the need for further exploration of their potential in regulating autophagy. Moreover, it provides novel insights and potential therapeutic strategies in ovarian cancer by utilizing natural products to modulate autophagy.

Modulating OCA2 Expression as a Promising Approach to Enhance Skin Brightness and Reduce Dark Spots

The oculocutaneous albinism II (OCA2) gene encodes a melanosomal transmembrane protein involved in melanogenesis. Recent genome-wide association studies have identified several single nucleotide polymorphisms within OCA2 genes that are involved in skin pigmentation. Nevertheless, there have been no attempts to modulate this gene to improve skin discoloration. Accordingly, our aim was to identify compounds that can reduce OCA2 expression and to develop a formula that can improve skin brightness and reduce hyperpigmented spots. In this study, we investigated the effects of OCA2 expression reduction on melanin levels, melanosome pH, and autophagy induction through siRNA knockdown. Additionally, we identified several bioactives that effectively reduce OCA2 expression. Ultimately, in a clinical trial, we demonstrated that topical application of those compounds significantly improved skin tone and dark spots compared to vitamin C, a typical brightening agent. These findings demonstrate that OCA2 is a promising target for the development of efficacious cosmetics and therapeutics designed to treat hyperpigmentation.

The Potential Effects of Red Wine and Its Components on Neurocognitive Disorders: A Narrative Review

BACKGROUND

The aging population is associated with a net increase in the incidence and prevalence of chronic-degenerative diseases, particularly neurocognitive disorders. Therefore, the identification of preventative strategies to restrain the burden of such chronic conditions is of key relevance. Red wine and its components have accumulated evidence regarding their positive effects in terms of neurological pathologies associated with neurocognitive symptoms.

METHODS

Based on this background, the present narrative review aims to summarize the state-of-the-art evidence on the effects of red wine and its components on neurocognitive disorders in both preclinical and clinical settings.

RESULTS

The main findings highlight a protective effect of wine polyphenols present in red wine on dementia in different preclinical models of cognitive decline. The current translational clinical evidence remains uncertain, especially considering the risk-to-benefit ratio of alcohol consumption on brain health.

CONCLUSIONS

Given the overall health risks associated with red wine consumption and consistent with the prevailing guidelines in the literature, there is insufficient evidence to support light-to-moderate red wine consumption as an effective strategy for preventing these diseases. However, the largely preclinical findings on polyphenols derived from red wine remain of significant interest in this context.

Dominantly acting variants in ATP6V1C1 and ATP6V1B2 cause a multisystem phenotypic spectrum by altering lysosomal and/or autophagosome function

The vacuolar H+-ATPase (V-ATPase) is a functionally conserved multimeric complex localized at the membranes of many organelles where its proton-pumping action is required for proper lumen acidification. The V-ATPase complex is composed of several subunits, some of which have been linked to human disease. We and others previously reported pathogenic dominantly acting variants in ATP6V1B2, the gene encoding the V1B2 subunit, as underlying a clinically variable phenotypic spectrum including dominant deafness-onychodystrophy (DDOD) syndrome, Zimmermann-Laband syndrome (ZLS), and deafness, onychodystrophy, osteodystrophy, intellectual disability, and seizures (DOORS) syndrome. Here, we report on an individual with features fitting DOORS syndrome caused by dysregulated ATP6V1C1 function, expand the clinical features associated with ATP6V1B2 pathogenic variants, and provide evidence that these ATP6V1C1/ATP6V1B2 amino acid substitutions result in a gain-of-function mechanism upregulating V-ATPase function that drives increased lysosomal acidification. We demonstrate a disruptive effect of these ATP6V1B2/ATP6V1C1 variants on lysosomal morphology, localization, and function, resulting in a defective autophagic flux and accumulation of lysosomal substrates. We also show that the upregulated V-ATPase function affects cilium biogenesis, further documenting pleiotropy. This work identifies ATP6V1C1 as a new gene associated with a neurodevelopmental phenotype resembling DOORS syndrome, documents the occurrence of a phenotypic continuum between ZLS, and DDOD and DOORS syndromes, and classify these conditions as lysosomal disorders.

Autophagy Alterations in White and Brown Adipose Tissues of Mice Exercised under Different Training Protocols

BACKGROUND

Autophagy is a conserved catabolic process that promotes cellular homeostasis and health. Although exercise is a well-established inducer of this pathway, little is known about the effects of different types of training protocols on the autophagy levels of tissues that are tightly linked to age-related metabolic syndromes (like brown adipose tissue) but are not easily accessible in humans.

METHODS

Here, we take advantage of animal models to assess the effects of short- and long-term resistance and endurance training in both white and brown adipose tissue, reporting distinct alterations on autophagy proteins microtubule-associated proteins 1A/1B light chain 3B (MAP1LC3B, or LC3B) and sequestosome-1 (SQSTM1/p62). Additionally, we also analyzed the repercussions of these interventions in fat tissues of mice lacking autophagy-related protein 4 homolog B (ATG4B), further assessing the impact of exercise in these dynamic, regulatory organs when autophagy is limited.

RESULTS

In wild-type mice, both short-term endurance and resistance training protocols increased the levels of autophagy markers in white adipose tissue before this similarity diverges during long training, while autophagy regulation appears to be far more complex in brown adipose tissue. Meanwhile, in ATG4B-deficient mice, only resistance training could slightly increase the presence of lipidated LC3B, while p62 levels increased in white adipose tissue after short-term training but decreased in brown adipose tissue after long-term training.

CONCLUSIONS

Altogether, our study suggests an intricated regulation of exercise-induced autophagy in adipose tissues that is dependent on the training protocol and the autophagy competence of the organism.

Microenvironment-responsive nano-bioconjugated vesicles for the multi-pronged treatment of liver fibrosis

Liver fibrosis represents an inevitable stage of various chronic liver diseases. The activated hepatic stellate cells (aHSCs) are the main drivers for promoting the development of liver fibrosis. Meanwhile, liver macrophages can secrete pro-inflammatory cytokines, thus accelerating the deterioration of the liver. Regulating both aHSCs and the inflammatory microenvironment in the liver simultaneously may be an effective strategy for treating liver fibrosis. A multi-pronged nano-bioconjugated system, HNP-B-aEV, was developed according to the above strategy. Based on cell aggregate-derived extracellular vesicles (aEVs) and hydroxychloroquine (HCQ)-loaded nanoparticles (HNP) modified with retinol, HNP-B-aEV is prepared via a reactive oxygen species (ROS)-responsive boronate linker. In the ROS-rich microenvironment of liver fibrosis, aEVs and HNP are released, eliminating ROS, and targeting aHSCs and macrophages respectively to inhibit the activation of HSCs. Both in vitro and in vivo studies demonstrated that HNP-B-aEV can significantly inhibit the release of inflammatory factors from M1 macrophages, remodeling the microenvironment and preventing the activation of HSCs, offering a multi-pronged treatment for liver fibrosis. This strategy can inhibit the progression of liver fibrosis at its source, providing a new perspective for the clinical treatment of liver fibrosis.

Hyperexcitability and translational phenotypes in a preclinical mouse model of SYNGAP1-related intellectual disability

Disruption of SYNGAP1 directly causes a genetically identifiable neurodevelopmental disorder (NDD) called SYNGAP1-related intellectual disability (SRID). Without functional SynGAP1 protein, individuals are developmentally delayed and have prominent features of intellectual disability (ID), motor impairments, and epilepsy. Over the past two decades, there have been numerous discoveries indicating the critical role of Syngap1. Several rodent models with a loss of Syngap1 have been engineered, identifying precise roles in neuronal structure and function, as well as key biochemical pathways key for synapse integrity. Homozygous loss of SYNGAP1/Syngap1 is lethal. Heterozygous mutations of Syngap1 result in a broad range of behavioral phenotypes. Our in vivo functional data, using the original mouse model from the Huganir laboratory, corroborated behaviors including robust hyperactivity and deficits in learning and memory in young adults. Furthermore, we described impairments in the domain of sleep, characterized using neurophysiological data that was collected with wireless, telemetric electroencephalography (EEG). Syngap1+/- mice exhibited elevated spiking events and spike trains, in addition to elevated power, most notably in the delta power frequency. For the first time, we illustrated that primary neurons from Syngap1+/- mice displayed: 1) increased network firing activity, 2) greater bursts, 3) and shorter inter-burst intervals between peaks, by utilizing high density microelectrode arrays (HD-MEA). Our work bridges in vitro electrophysiological neuronal activity and function with in vivo neurophysiological brain activity and function. These data elucidate quantitative, translational biomarkers in vivo and in vitro that can be utilized for the development and efficacy assessment of targeted treatments for SRID.

A Unique Case of Vascular Variations in the Upper Limbs: A Brachioradial Artery and Bilateral Persistent Median Arteries With Incomplete Superficial Palmar Arches

Numerous vascular variations were observed in the upper limbs of a 109-year-old female donor to the Gift Body Program of Saint Louis University School of Medicine. Variations in the right upper limb included the presence of a brachioradial artery (BRA), persistent median artery (PMA), and an ulnar-dominant incomplete type B superficial palmar arch (SPA). In the left upper limb, the brachial artery bifurcated normally into the ulnar artery (UA) and radial artery (RA). However, a more developed palmar type of PMA was observed, replacing much of the palmar circulation typically supplied by the superficial palmar branch of the RA, which existed only as a small branch anastomosing with the PMA to form a rare arcus medianoradialis-type SPA. Both PMAs arose from their respective UAs distal to the origin of the common interosseous arteries. The left PMA pierced the median nerve (MN) as it descended the forearm. The extent of these variations together presents a unique case of vascularity in the upper limbs. Knowledge of these variations is pertinent to MN compression pathologies as well as procedures involving the upper limb.

VEGF and ELAVL1/HuR protein levels are increased in dry and wet AMD patients. A new tile in the pathophysiologic mechanisms underlying RPE degeneration?

Age-related macular degeneration (AMD) is a common retinal pathology characterized by degeneration of macula's retinal pigment epithelium (RPE) and photoreceptors, visual impairment, or loss. Compared to wet AMD, dry AMD is more common, but lacks cures; therefore, identification of new potential therapeutic targets and treatments is urgent. Increased oxidative stress and declining antioxidant, detoxifying systems contribute to the pathophysiologic mechanisms underlying AMD. The present work shows that the Embryonic Lethal Abnormal Vision-Like 1/Human antigen R (ELAVL1/HuR) and the Vascular Endothelial Growth Factor (VEGF) protein levels are higher in the RPE of both dry and wet AMD patients compared to healthy subjects. Moreover, increased HuR protein levels are detected in the retina, and especially in the RPE layer, of a dry AMD model, the nuclear factor erythroid 2-related factor 2 (Nrf2) / peroxisome proliferator-activated receptor gamma coactivator-1α (PGC-1α) double knock-out mouse. The crosstalk among Nrf2, HuR and VEGF has been also studied in ARPE-19 cells in basal and stressful conditions related to the AMD context (i.e., oxidative stress, autophagy impairment, Nrf2 deficit), offering new evidence of the mutual influence between Nrf2 and HuR, of the dependence of VEGF expression and secretion by these two factors, and of the increased susceptibility of cells to stressful conditions in Nrf2- or HuR-impaired contexts. Overall, this study shows evidence of the interplay among Nrf2, HuR and VEGF, essential factors for RPE homeostasis, and represents an additional piece in the understanding of the complex pathophysiologic mechanisms underlying AMD.

Targeting the autophagy-miRNA axis in prostate cancer: toward novel diagnostic and therapeutic strategies

Since prostate cancer is one of the leading causes of cancer-related death, a better understanding of the molecular pathways guiding its development is imperative. A key factor in prostate cancer is autophagy, a cellular mechanism that affects both cell survival and death. Autophagy is essential in maintaining cellular homeostasis. Autophagy is a physiological mechanism wherein redundant or malfunctioning cellular constituents are broken down and recycled. It is essential for preserving cellular homeostasis and is implicated in several physiological and pathological conditions, including cancer. Autophagy has been linked to metastasis, tumor development, and treatment resistance in prostate cancer. The deregulation of miRNAs related to autophagy appears to be a crucial element in the etiology of prostate cancer. These miRNAs influence the destiny of cancer cells by finely regulating autophagic mechanisms. Numerous investigations have emphasized the dual function of specific miRNAs in prostate cancer, which alter autophagy-related pathways to function as either tumor suppressors or oncogenes. Notably, miRNAs have been linked to the control of autophagy and the proliferation, apoptosis, and migration of prostate cancer cells. To create customized therapy approaches, it is imperative to comprehend the dynamic interplay between autophagy and miRNAs in prostate cancer. The identification of key miRNAs provides potential diagnostic and prognostic markers. Unraveling the complex network of lncRNAs, like PCA3, also expands the repertoire of molecular targets for therapeutic interventions. This review explores the intricate interplay between autophagy and miRNAs in prostate cancer, focusing on their regulatory roles in cellular processes ranging from survival to programmed cell death.

Baicalin induces cell death of non-small cell lung cancer cells via MCOLN3-mediated lysosomal dysfunction and autophagy blockage

BACKGROUND

Non-small cell lung cancer (NSCLC) accounts for 85 % of lung cancer, becoming the most mortality of all cancers globally. Blockage of autophagy in NSCLC represents a promising therapeutic strategy that inhibits angiogenesis and overcomes drug resistance. Natural ingredients in anti-tumor adjuvants are increasingly reported to promote cell death with less side effects and the potential to increase chemotherapeutic drugs sensitivity. Baicalin, a Scutellaria baicalensis-extracted flavonoid glycoside, is reported to induce death of NSCLC cells, however, its effects on autophagy in NSCLC cells remain unclear.

PURPOSE

This study aimed to investigate the effect of baicalin on autophagic flux in NSCLC cells, unraveling the underlying mechanism including potential target and its role in cell death of NSCLC cells.

METHODS

In vitro anti-cancer effects of baicalin were verified by evaluating proliferation, clone formation, cell cycle, and cell migration in three NSCLC cell lines (A549, H1299, and PC-9). In vivo anti-tumor efficacies of baicalin were evaluated in subcutaneous xenograft tumor model in nude mice. Autophagy characterization in NSCLC cells included autophagic marker detection by western blot and immunofluorescence staining, subcellular structure observation by TEM, lysosomal function by RNA-seq and fluorescence staining (LysoTracker®, LysoSensor®, and acridine orange). Based on RNA-seq and molecular biological verification using apoptotic, autophagic, and lysosomal inhibitors, potential target molecule of baicalin was verified via Ca2+ flux assay, MCOLN3 knockdown by shRNA, and virtual molecular docking.

RESULTS

Baicalin inhibited NSCLC cell proliferation and migration, and suppressed tumor growth in vivo. Baicalin blocked the autophagic flux via activating the membranal cation channel MCOLN3 of lysosome, which disrupted its Ca2+ balance and induced lysosome dysfunction, leading to failure of autolysosome degradation. The cytoplasmic Ca2+ imbalance further resulted in depolarization of mitochondrial membrane potentials and ROS accumulation in NSCLC cells, mediating autophagy-related apoptosis.

CONCLUSION

This study demonstrated that baicalin inhibited autolysosome degradation by activating MCOLN3, leading to dysfunction in lysosomal pH elevation, thereby inhibiting autophagy in NSCLC, leading to apoptotic death of NSCLC cells. These findings enriched the existing theories of cancer therapy based on autophagy inhibition and underlying mechanisms of flavonoids as antitumor agents, paving the way for their clinical application in future.

Acute and Post-Acute COVID-19 Cardiovascular Complications: A Comprehensive Review

PURPOSE OF REVIEW

The risk of cardiovascular complications due to SARS-CoV-2 are significantly increased within the first 6 months of the infection. Patients with COVID-19 have an increased risk of death, and there is evidence that many may experience a wide range of post-acute cardiovascular complications. Our work aims to provide an update on current clinical aspects of diagnosis and treatment of cardiovascular manifestations during acute and long-term COVID-19.

RECENT FINDINGS

SARS-CoV-2 has been shown to be associated with increased incidence of cardiovascular complications such as myocardial injury, heart failure, and dysrhythmias, as well as coagulation abnormalities not only during the acute phase but also beyond the first 30 days of the infection, associated with high mortality and poor outcomes. Cardiovascular complications during long-COVID-19 were found regardless of comorbidities such as age, hypertension, and diabetes; nevertheless, these populations remain at high risk for the worst outcomes during post-acute COVID-19. Emphasis should be given to the management of these patients. Treatment with low-dose oral propranolol, a beta blocker, for heart rate management may be considered, since it was found to significantly attenuate tachycardia and improve symptoms in postural tachycardia syndrome, while for patients on ACE inhibitors or angiotensin-receptor blockers (ARBs), under no circumstances should these medications be withdrawn. In addition, in patients at high risk after hospitalization due to COVID-19, thromboprophylaxis with rivaroxaban 10 mg/day for 35 days improved clinical outcomes compared with no extended thromboprophylaxis. In this work we provide a comprehensive review on acute and post-acute COVID-19 cardiovascular complications, symptomatology, and pathophysiology mechanisms. We also discuss therapeutic strategies for these patients during acute and long-term care and highlight populations at risk. Our findings suggest that older patients with risk factors such as hypertension, diabetes, and medical history of vascular disease have worse outcomes during acute SARS-CoV-2 infection and are more likely to develop cardiovascular complications during long-COVID-19.