OBJECTIVE: Doxorubicin is widely used in the treatment of malignant tumours, but doxorubicin-induced cardiotoxicity severely limits its clinical application. Spexin is a neuropeptide that acts as a novel biomarker in cardiovascular disease. However, the effects of spexin on doxorubicin-induced cardiotoxicity is unclear.
METHODS: We established a model of doxorubicin-induced cardiotoxicity both in vivo and in vitro. Levels of cardiac damage in mice was assessed through cardiac function assessment, determination of serum cardiac troponin T and CKMB levels and histological examination. CCK8 and PI staining were used to assess the doxorubicin-induced toxicity in cultures of cardiomyocytes in vitro. Ferroptosis was assessed using FerroOrange staining, determination of MDA and 4-HNE content and ferroptosis-associated proteins SLC7A11 and GPX4. Mitochondrial membrane potential and lipid peroxidation levels were measured using TMRE and C11-BODIPY 581/591 probes, respectively. Myocardial autophagy was assessed by expression of P62 and Beclin1.
RESULTS: Spexin treatment improved heart function of mice with doxorubicin-induced cardiotoxicity, and attenuated doxorubicin-induced cardiotoxicity by decreasing iron accumulation, abnormal lipid metabolism and inhibiting ferroptosis. Interestingly, doxorubicin caused excessive autophagy in cardiomyocyte in culture, which could be alleviated by treatment with spexin. Knockdown of Beclin 1 eliminated the protective effects of spexin in mice with DIC.
CONCLUSIONS: Spexin ameliorated doxorubicin-induced cardiotoxicity by inhibiting excessive autophagy-induced ferroptosis, suggesting that spexin could be a drug candidate against doxorubicin-induced cardiotoxicity. Beclin 1 might be critical in mediating the protective effect of spexin against doxorubicin-induced cardiotoxicity.

Chronic pain is associated with alterations in fundamental cellular processes. Here, we investigate whether Beclin 1, a protein essential for initiating the cellular process of autophagy, is involved in pain processing and is targetable for pain relief. We find that monoallelic deletion of Becn1 increases inflammation-induced mechanical hypersensitivity in male mice. However, in females, loss of Becn1 does not affect inflammation-induced mechanical hypersensitivity. In males, intrathecal delivery of a Beclin 1 activator, tat-beclin 1, reverses inflammation- and nerve injury-induced mechanical hypersensitivity and prevents mechanical hypersensitivity induced by brain-derived neurotrophic factor (BDNF), a mediator of inflammatory and neuropathic pain. Pain signaling pathways converge on the enhancement of N-methyl-D-aspartate receptors (NMDARs) in spinal dorsal horn neurons. The loss of Becn1 upregulates synaptic NMDAR-mediated currents in dorsal horn neurons from males but not females. We conclude that inhibition of Beclin 1 in the dorsal horn is critical in mediating inflammatory and neuropathic pain signaling pathways in males.

Hepatic steatosis has become the most common cause of chronic liver disease among children worldwide.  Lipophagy has been considered as a pathway affecting steatosis development and progression.
OBJECTIVE: this study aimed to evaluate the immunohistochemical expression of Beclin1 and LC3A in pediatric hepatic tissues with steatosis and to correlate their expression with clinicopathological parameters.
METHODS: this study included 81 Egyptian pediatric patients with hepatic steatosis and 21 pediatric cases without hepatic steatosis. All specimens were stained by Beclin1 and LC3A antibodies. According to final diagnosis obtained from Pediatric Hepatology department, patients were divided into two groups: chronic liver disease (CLD) group that included 45 cases and inborn error of metabolism (IEM) group that included 36 cases.
RESULTS: higher beclin1 expression was significantly correlated with higher stages of fibrosis and distorted liver architecture in CLD group, (P=0.043) for both. The control group showed higher positivity, percentage, as well as the median values of the H score of LC3A expression than did the CLD group or the IEM group (P=0.055, 0.001, and 0.008, respectively). Higher positivity of LC3A was significantly associated with higher stages of fibrosis and distorted liver architecture in the studied IEM group (P=0.021) for both.
CONCLUSIONS: Varying intensity grades of LC3A and Beclin 1 immunohistochemical expression demonstrate the variation of autophagy at different phases of pediatric hepatic steatosis and varied disease etiology.

Breast cancer (BC) is a heterogenous disease with multiple pathways implicated in its development, progression, and drug resistance. Autophagy, a cellular process responsible for self-digestion of damaged organelles, had been recognized as eminent player in cancer progression and chemotherapeutic resistance. The haploinsufficiency of Beclin 1 (BECN1), autophagy protein, is believed to contribute to cancer pathogenesis and progression. In our study, we investigated the expression of BECN1 in a BC female Egyptian patient cohort, as well as its prognostic role through evaluating its association with disease free survival (DFS) after 2 years follow up and association of tumor clinicopathological features. Twenty frozen female BC tissue samples and 17 adjacent normal tissue were included and examined for the expression levels of BECN1. Although the tumor tissues showed lower expression 0.73 (0-8.95) than their corresponding normal tissues 1.02 (0.04-19.59), it was not statistically significant, p: 0.463. BECN1 expression was not associated with stage, nodal metastasis or tumor size, p:0.435, 0.541, 0.296, respectively. However, statistically significant negative correlation was found between grade and BECN1 mRNA expression in the studied cases, p:0.028. BECN1 expression had no statistically significant association with DFS, P = 0.944. However, we observed that triple negative (TNBC) cases had significantly lower DFS rate than luminal BC patients, p: 0.022, with mean DFS 19.0 months, while luminal BC patients had mean DFS of 23.41 months. Our study highlights the potential role of BECN1 in BC pathogenesis, showing that BECN1 expression correlates with poorer differentiation of BC, indicating its probable link with disease aggressiveness. DFS two years follow up showed that TNBC subtype remains associated with less favorable prognosis.

PDZ protein interacting specifically with Tc10 or PIST is a mammalian trans-Golgi resident protein that regulates subcellular sorting of plasma membrane receptors. PIST has recently emerged as a key player in regulating viral pathogenesis. Nevertheless, the involvement of PIST in parasitic infections remains unexplored. Leishmania parasites infiltrate their host macrophage cells through phagocytosis, where they subsequently multiply within the parasitophorous vacuole (PV). Host cell autophagy has been found to be important in regulating this parasite infection. Since PIST plays a pivotal role in triggering autophagy through the Beclin 1-PI3KC3 pathway, it becomes interesting to identify the status of PIST during Leishmania infection. We found that while macrophage cells are infected with Leishmania major (L. major), the expression of PIST protein remains unaltered; however, it traffics from the Golgi compartment to PV. Further, we identified that in L. major-infected macrophage cells, PIST associates with the autophagy regulatory protein Beclin 1 within the PVs; however, PIST does not interact with LC3. Reduction in PIST protein through siRNA silencing significantly increased parasite burden, whereas overexpression of PIST in macrophages restricted L. major infectivity. Together, our study reports that the macrophage PIST protein is essential in regulating L. major infectivity.

Diabetic retinopathy (DR) is a debilitating diabetic disorder of the retinal microvasculature and the main cause of avoidable blindness in old people. Hesperetin is a plant flavanone largely abundant in citrus species with neuroprotective properties in animal models. This study aimed to explore the neuroprotective and autophagy-enhancing effect of hesperetin in rats with DR. Twenty-four male rats were utilized and allocated to groups: (i) the vehicle group, (ii) DR group and (iii-iv) the DR + hesperetin (50 and 100 mg/kg) groups. Treatment with hesperetin continued for 6 weeks. After the rats were euthanized, their eyes were dissected to detect the biochemical and histological changes in the retinas. Quantification of autophagy markers, beclin 1/LC3/p62, and inflammation markers was performed. Histopathologic changes were investigated after staining with hematoxylin and eosin and periodic acid-Schiff (PAS). Results demonstrated that hesperetin decreased the PAS staining in diabetic rats and attenuated histopathological changes and restored retinal organization and thickness of layers in hematoxylin and eosin staining. Moreover, hesperetin reduced the level of mRNA expression for TNF-α (4.9-fold), IL-1β (4.15-fold), IL-6 (4.6-fold) and NFκB (5.2-fold), as well as the protein level. This was accompanied by induction of autophagy proteins, beclin 1 and LC3-II. Our results afford evidence that hesperetin is effective in alleviating the pathology of DR via suppressing the inflammatory burden and induction of autophagy. After extensive clinical examinations, hesperetin may prove to be a useful option for treatment of DR.

BACKGROUND: Cardiovascular calcification is a pervasive issue throughout chronic kidney disease (CKD) progression. Autophagy, a fundamental cellular process, exerts significant influence on various cardiac pathologies, including arrhythmias, atherosclerosis, heart failure, and notably, valvular, and vascular calcifications. Beclin-1, a crucial eukaryotic protein, plays a major regulatory role in autophagy as part of the phosphatidylinositol-3-kinase (PI3K) complex. Recent evidence suggests a protective role for Beclin-1-mediated autophagy in CKD vascular calcification, raising its potential as a novel therapeutic target in this context.
UNASSIGNED: Investigate the association between serum Beclin 1 levels and the presence of cardiovascular valvular calcification in hemodialysis patients.
RESULTS: This study evaluated a cohort of 102 hemodialysis patients, evenly divided into two groups based on echocardiographic findings. All participants underwent serum Beclin 1 measurement and transthoracic echocardiography. Patients with acute kidney injury, active malignancy, or diabetes were excluded. Our study revealed significant differences between the two groups in terms of: Serum Beclin 1 levels, all parameters of lipid profile, prevalence of ischemic heart disease, serum albumin levels and Total calcium. Echocardiography in Group 1 showed that most cases (60.78%) exhibited mild aortic valve calcification. Additionally, significant relationships were observed between Beclin 1 and: ischemic heart disease (p=0.011) Aortic valve calcification on echocardiography (p < 0.001) Interestingly, lower Beclin 1 levels were associated with more severe valve calcification. A Beclin 1 cutoff value of ≤ 35.5 ng/ml demonstrated the highest sensitivity (98%) and specificity (92%).
CONCLUSIONS: Our findings suggest that the serum Beclin 1 level could be incorporated into a predictive model for cardiac valvular calcification in hemodialysis patients.

BACKGROUND: Acute myocardial infarction (AMI) is a main contributor of sudden cardiac death worldwide. The discovery of new biomarkers that can improve AMI risk prediction meets a major clinical need for the identification of high-risk patients and the tailoring of medical treatment. Previously, we reported that autophagy a highly conserved catabolic mechanism for intracellular degradation of cellular components is involved in atherosclerotic plaque phenotype and cardiac pathological remodeling. The crucial role of autophagy in the normal and diseased heart has been well described, and its activation functions as a pro-survival process in response to myocardial ischemia. However, autophagy is dysregulated in ischemia/reperfusion injury, thus promoting necrotic or apoptotic cardiac cell death. Very few studies have focused on the plasma levels of autophagy markers in cardiovascular disease patients, even though they could be companion biomarkers of AMI injury. The aims of the present study were to evaluate (1) whether variations in plasma levels of two key autophagy regulators autophagy-related gene 5 (ATG5) and Beclin 1 (the mammalian yeast ortholog Atg6/Vps30) are associated with AMI and (2) their potential for predicting AMI risk.
METHODS: The case-control study population included AMI patients (n = 100) and control subjects (n = 99) at high cardiovascular risk but without known coronary disease. Plasma levels of ATG5 and Beclin 1 were measured in the whole population study by enzyme-linked immunosorbent assay.
RESULTS: Multivariate analyses adjusted on common cardiovascular factors and medical treatments, and receiver operating characteristic curves demonstrated that ATG5 and Beclin 1 levels were inversely associated with AMI and provided original biomarkers for AMI risk prediction.
CONCLUSIONS: Plasma levels of autophagy regulators ATG5 and Beclin 1 represent relevant candidate biomarkers associated with AMI.

Focal adhesions (FAs) play a crucial role in cell spreading and adhesion, and their autophagic degradation is an emerging area of interest. This study investigates the role of Thrombospondin Type 1 Domain-Containing Protein 1 (THSD1) in regulating autophagy and FA stability in brain endothelial cells, shedding light on its potential implications for cerebrovascular diseases. Our research reveals a physical interaction between THSD1 and FAs. Depletion of THSD1 significantly reduces FA numbers, impairing cell spreading and adhesion. The loss of THSD1 also induces autophagy independently of changes in mTOR and AMPK activation, implying that THSD1 primarily governs FA dynamics rather than serving as a global regulator of nutrient and energy status. Mechanistically, THSD1 negatively regulates Beclin 1, a central autophagy regulator, at FAs through interactions with focal adhesion kinase (FAK). THSD1 inactivation diminishes FAK activity and relieves its inhibitory phosphorylation on Beclin 1. This, in turn, promotes the complex formation between Beclin 1 and ATG14, a critical event for the activation of the autophagy cascade. In summary, our findings identify THSD1 as a novel regulator of autophagy that degrades FAs in brain endothelial cells. This underscores the distinctive nature of THSD1-mediated, cargo-directed autophagy and its potential relevance to vascular diseases due to the loss of endothelial FAs. Investigating the underlying mechanisms of THSD1-mediated pathways holds promise for discovering novel therapeutic targets in vascular diseases.

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