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Coronary artery bypass grafting (CABG) remains the gold standard for patients with advanced multivessel coronary artery disease. Optimal myocardial protection versus ischemia during reversible and controlled cardiac arrest is a cornerstone of successful outcomes. Myocardial ischemia represents a state of reduced coronary perfusion with oxygenated blood, insufficient to meet the metabolic demands of the myocardium. Conventional cardioplegic solutions offer controlled and reversible cardiac arrest while actively modulating the molecular and cellular mechanisms that mediate ischemia-reperfusion injury. Cardioplegia dramatically elongates the reversible period of ischemic injury and restricts cardiomyocyte death by shutting down electromechanical activity, lowering metabolic demand, stabilizing ionic homeostasis, protecting mitochondrial integrity, and slowing oxidative stress and inflammatory signaling. During ischemia, cardiomyocytes shift from aerobic to anaerobic metabolism, resulting in adenosine triphosphate (ATP) depletion, loss of ionic homeostasis and calcium overload that activate proteases, phospholipases and membrane damage. Reperfusion restores oxygen supply and prevents irreversible necrosis but paradoxically initiates additional injury in marginally viable myocardium. The reoxygenation phase induces excessive production of reactive oxygen species (ROS), endothelial dysfunction and a strong inflammatory response mediated by neutrophils, platelets and cytokines. Mitochondrial dysfunction and opening of the mitochondrial permeability transition pore (mPTP) further amplify oxidative stress and inflammation, and trigger apoptosis and necroptosis. Understanding these intertwined cellular and molecular mechanisms remains essential for identifying novel therapeutic targets aimed at reducing reperfusion injury and improving myocardial recovery after ischemic events, particularly in coronary surgery.

Individuals born after intrauterine growth restriction (IUGR) are at increased risk of long-term cardiovascular complications, including elevated blood pressure, endothelial dysfunction, and arterial stiffness. Endothelial progenitor cells (EPCs), particularly endothelial colony-forming cells (ECFCs), play a critical role in maintaining vascular homeostasis. Previously, Simoncini et al. observed that in a rat model of IUGR, six-month-old males exhibited elevated systolic blood pressure (SBP) and microvascular rarefaction compared with control (CTRL) rats. These vascular alterations were accompanied by reduced numbers and impaired function of bone marrow-derived ECFCs, which were associated with oxidative stress and stress-induced premature senescence (SIPS). In contrast, IUGR females of the same age and from the same litter did not exhibit higher SBP or microvascular rarefaction, raising the question of whether ECFC dysfunction in IUGR female rats can be present without vascular alterations. So, we investigated ECFCs isolated from six-month-old female IUGR offspring (maternal 9% casein diet) and CTRL females (23% casein diet). To complete the vascular assessment, we performed in vivo and in vitro investigations. No alteration in pulse wave velocity (measured by echo-Doppler) was observed; however, IUGR females showed decreased aortic collagen and increased elastin content compared with CTRL. Regarding ECFCs, those from IUGR females maintained their endothelial identity (CD31⁺/CD146⁺ ratio among viable CD45^- cells) but exhibited slight alterations in progenitor marker expression (CD34) compared with those of CTRL females. Functionally, IUGR-ECFCs displayed a delayed proliferation phase between 6 and 24 h, while their ability to form capillary-like structures remained unchanged, however their capacity to form capillary-like structures was preserved. Regarding the nitric oxide (NO) pathway, a biologically relevant trend toward reduced NO levels and decreased endothelial nitric oxide synthase expression was observed, whereas oxidative stress and SIPS markers remained unchanged. Overall, these findings indicate that ECFCs from six-month-old female IUGR rats exhibit only minor functional alterations, which may contribute to vascular protection against increase SBP, microvascular rarefaction, and arterial stiffness.

Necroptosis and dysfunction of ovarian granulosa cells are major contributors to follicular atresia and reduced fertility in cattle, processes that are closely associated with endoplasmic reticulum stress (ERS). Ginseng polysaccharides (GPSs) are known to reduce ER stress, display anti-inflammatory properties, and modulate reproductive function; however, whether GPS can protect against granulosa cell injury and the underlying mechanisms remain unclear. To address this gap, this study aimed to investigate the protective effects of GPS on ERS-induced bovine granulosa cell damage and to elucidate the associated mechanisms. An ERS model was established in bovine granulosa cells using tunicamycin (Tm), and cellular responses were evaluated via flow cytometry, ELISA, and EdU assays. Further, a mouse model was used to validate the protective effects of GPS against Tm-induced ovarian injury. The results showed that 40 μg/mL of GPS significantly alleviated ERS-induced granulosa cell damage, inhibited necroptosis, and mitigated ERS. Moreover, using the PI3K/Akt pathway inhibitor LY294002, we demonstrated that the inhibitor antagonized the effects of GPS, indicating that GPS promotes granulosa cell proliferation and restores estrogen secretion via activating the PI3K/Akt pathway. In vivo experiments further confirmed that GPS effectively attenuates ERS-induced ovarian damage in mice. Collectively, these findings reveal that GPS improves granulosa cell function and ovarian tissue integrity by modulating the ERS network and the PI3K/Akt pathway, yielding a theoretical basis for preventing follicular atresia and enhancing reproductive efficiency in cattle.

Prostate cancer (PCa) metastasis is reliant on the activity of proteases, such as matrix metalloproteinase-2 (MMP-2). While increased extracellular heat shock protein 90α (eHSP90α) has been linked to increased MMP-2 activity, this has not been examined in the context of cellular stress. We examined stress-induced eHSP90α in human prostate cell lines by immunoblot. Fluorometric gelatin dequenching and zymography assays measured MMP activity. Wound healing and Matrigel drop invasion assays were used to quantify cell motility. HSP90α knockout (KO) cells were established with CRISPR/Cas9. Proteases were profiled with molecular inhibitors and protein arrays and validated by siRNA knockdown, immunoblot, and motility assays. Stress increased eHSP90 in four out of four human prostate cell lines examined. Surprisingly, it concurrently decreased MMP-2 activity. The functional relevance of this was demonstrated when conditioned media from stressed cells decreased the motility of non-stressed cells. Screening for protease inhibitors that would rescue stress-induced decreases in MMP-2 activity identified a single serine protease inhibitor: aprotinin. Yet rescue with aprotinin was lost in HSP90α KO cells. A protease array identified stress-induced increases in kallikrein-related peptidase 6 (KLK6). Knockdown of KLK6 rescued stress-induced MMP-2 activity and cell motility. In conclusion, we identify a novel stress-induced extracellular network that regulates MMP-2 activity and cell motility. We identified KLK6 as a stress-induced extracellular protease leading to decreased MMP-2 activity and cellular invasion, while eHSP90α is required for the rescue of MMP-2 activity once KLK6 is neutralized.

Chimeric antigen receptor (CAR) T cell therapy has demonstrated clinical success in hematologic malignancies but has limited efficacy in solid tumors due to tumor microenvironment (TME) barriers that impede CAR T cell recognition, infiltration, and sustained function. Traditional 2D assays inadequately recapitulate these constraints, necessitating improved in vitro models. This study validated a 3D tumor spheroid platform using an agarose microwell system to generate uniform B7-H3-positive spheroids from multiple solid tumor cell lines, enabling the evaluation of CAR T cell activity. TME-relevant immune modulation under 3D conditions was analyzed by flow cytometry for B7-H3, MHC I/II, and antigen processing machinery (APM), followed by co-culture with B7-H3 CAR T cells to assess cytotoxicity, spheroid integrity, tumor viability, and CAR T cell activation, exhaustion, and cytokine production. Two human cancer-cell-line-derived spheroids, DU 145 (prostate cancer) and SUM159 (breast cancer), retained B7-H3 expression, while MC38 (mouse colon cancer)-derived spheroids served as a B7-H3 negative control. Under 3D culture conditions, DU 145 and SUM159 spheroids acquire TME-like immune evasion characteristics and specifically downregulated MHC-I and APM (TAP1, TAP2, LMP7) with concurrent upregulation of MHC-II and calreticulin. Co-culture showed effective spheroid infiltration, cytotoxicity, and structural disruption, with infiltrating CAR T cells displaying higher CD4⁺ fraction, activation, exhaustion, effector/terminal differentiation, and IFN-γ/TNF-α production. This 3D platform recapitulates critical TME constraints and provides a cost-effective, feasible preclinical tool to assess CAR T therapies beyond conventional 2D assays.

Early prevention of pathological changes underlying gastric cancer (GC) development is a critical strategy, offering the most effective opportunity to limit malignant progression and improve patient outcomes. We have previously demonstrated that Helicobacter pylori (Hp) (cagA⁺vacA⁺) contributes to GC development by activating gastric fibroblasts toward CAF-like phenotype, eliciting aggressive, cancer stem cells (CSCs)-related malignant transformation of LGR5⁺ normal epithelial cells. A key mediator of these processes appears to be the NF-κB/STAT3 axis. Therefore, our aim was to investigate the protective role of hydrogen sulfide (H₂S) as a potential novel strategy for counteracting Hp-induced fibroblast reprogramming. Human fibroblasts were infected with Hp (cagA+vacA+) for 120 h. The fast-releasing H₂S donor NaHS (50, 100, 200 and 400 µM) was added every 24 h. Activation markers, corresponding signaling pathways, H₂S release and activities of H₂S-metabolizing enzymes were determined. NaHS reduced Hp-induced fibroblast activation and their pro-inflammatory, pro-tumorigenic markers, which was associated with the inhibition of NF-κB/STAT3 axis and Twist expression. Additionally, it modulated sulfur metabolism while preserving sulfur-enzyme homeostasis. NaHS limited Hp adhesion (high doses), reduced reinfection-induced activation and increased sensitivity of Hp to metronidazole. These findings suggest that H₂S signaling may represent a modulatory factor of NF-κB/STAT3-driven inflammatory responses during Hp infection and warrant further investigation.

The immunosuppressive T regulatory cells (Tregs) regulate immune responses and maintain immune homeostasis, yet their functions in metabolic dysfunction-associated steatotic liver disease (MASLD) remain controversial. Here we report increased accumulation of Tregs and effector T cells within the liver parenchyma of mice fed a Western diet (WD). This pattern was also observed in MASH patients, where an increase in intrahepatic Tregs was noted. In the absence of adaptive immune cells in Rag1 KO mice, WD promoted accumulation of intrahepatic neutrophils and macrophages and exacerbated hepatic inflammation and fibrosis. Similarly, targeted Treg depletion exacerbated WD-induced hepatic inflammation and fibrosis. In Treg-depleted mice, hepatic injury was associated with increased accumulation of neutrophils, macrophages, and activated T cells in the liver. Conversely, induction of Treg numbers using recombinant IL2/αIL2 mAb cocktail reduced hepatic steatosis, inflammation, and fibrosis in WD-fed mice. Analysis of intrahepatic Tregs from WD-fed mice revealed a phenotypic signature of impaired Treg function in MASLD. Ex vivo functional studies showed that glucose and palmitate, but not fructose, impaired the immunosuppressive ability of Treg cells. The findings indicate that the liver microenvironment in MASLD impairs the ability of Tregs to suppress effector immune cell activation, thus perpetuating chronic inflammation and driving MASLD progression.

As we become older, systems throughout the body gradually decline in function. Contributing factors include the accumulation of senescent cells and the dysfunction and exhaustion of stem and progenitor cells. A promising approach to mitigate these changes and enhance cellular function in aged animals is the discovery that differentiated cells retain plasticity, enabling them to revert to pluripotent states when exposed to Yamanaka factors. This method has shown promise in models of rapid aging, and recent studies have demonstrated notable life extension in both flies and mice. These findings, along with the development of senolytics and aging clocks, could revolutionize aging research and interventions. Here, we review recent discoveries in the field and propose new directions for intervention discovery.

Background: Recombinant human arginase (rhArg) has been proven to exhibit an anticancer effect via arginine starvation. To further improve the efficacy of rhArg, we examined the feasibility of a combination strategy with Bcl-2 inhibitors (ABT263 and ABT199) or an antidiabetic drug (metformin) and investigated the mechanistic basis for these strategies.

Methods: The combination effects were evaluated in a panel of human cancer cell lines modeling pancreatic ductal carcinoma (PDAC), triple-negative breast cancer (TNBC), colorectal cancer (CRC) and glioblastoma (GBM). Western blot analysis was used to evaluate the expression of apoptotic and cell cycle markers. MTT assay was used to evaluate the combination efficacy. Flow cytometric assays were used to investigate the apoptotic and cell cycle effects.

Results: The combination of rhArg with sublethal doses of ABT263 significantly induced dose-dependent apoptosis, with elevated expression of apoptotic markers and a CI of 0.47 in U251. The combination inhibited CDK2 and cyclin A expression, indicating that the observed synergy also resulted from cell cycle arrest. We also found that rhArg + metformin was synergistic in a time-dependent manner. Compared to other amino acid depletion agents, rhArg + ABT263 was the most favorable combination pair.

Conclusions: The combination of rhArg and ABT263 enhanced apoptosis and cell cycle arrest, demonstrating a potential broad-spectrum antitumor strategy.

Vitamin A in the form of 11-cis-retinaldehyde is the chromophore essential to vision. Thus, deficiencies in vitamin A necessitate the implementation of vitamin A supplementation. Moreover, some vitamin A is lost from the visual cycle due to random reactions that generate diretinaldehyde (bisretinoid) molecules; the latter are photoreactive and contribute to retinal disease. Here, we measured the systemic and ocular uptake of vitamin A along with bisretinoid as a function of vitamin A availability when supplied in the diet or by weekly i.p. injection in light- and dark-reared mice. Retinyl palmitate delivered as an i.p. bolus served to elevate plasma ROL but an associated increase in ocular 11-cisRAL was not observed in light- or dark-reared mice. In dark-reared mice, 11-cisRAL was more abundant when retinyl palmitate was provided in chow versus weekly i.p. injection; moreover, by the latter route, retinyl acetate was more effective. Conversely in dark-reared mice given retinyl palmitate by weekly i.p. injection versus chow, ocular atRAL was elevated. Liver atRE was elevated by increased retinyl palmitate in chow; the latter also favored elevated 11-cisRAL in dark-reared mice. In cyclic light-reared mice, ocular stores of atRE were increased by i.p. retinyl palmitate. With dark-rearing, there was no difference in bisretinoid (A2E) with retinyl palmitate in chow, nor by weekly i.p. injection; notably, bisretinoid levels were lower in cyclic light-reared mice due to photooxidative loss. In summary, light modulates the ocular retinoid, plasma atROL does not predict ocular levels of retinoid or bisretinoid and atRAL is elevated with sustained darkness.