Protective Effects of Cereal Grain Extracts on Alcohol-Induced Hepatocyte Damage.

This study investigated the protective effects of cereal grains on alcohol-induced hepatocyte damage. Cereal grains were extracted with methanol, and their radical scavenging properties and total phenolic contents were examined. Black rice extract exhibited the highest total polyphenol content and radical scavenging capacity. Treatment with sorghum extract increased the viability of cells exposed to alcohol by up to 81.6%. All cereal grain extracts decreased reactive oxygen species and malondialdehyde production and glutathione depletion in HepG2 cells exposed to ethanol. In particular, black rice and sorghum extracts exhibited greater antioxidant effects than other cereal grains. Treatment with black rice extract increased the levels of alanine aminotransferase and aspartate aminotransferase of alcohol-exposed cells to control levels. Overall, black rice extract showed a greater protective effect compared with other cereal grains against alcohol exposure in HepG2 cells and could improve alcohol-induced liver problems.

Pharmacological profile of agmatine: An in-depth overview.

Agmatine, a naturally occurring polyamine derived from arginine via arginine decarboxylase, has been shown to play multifaceted roles in the mammalian body, impacting a wide range of physiological and pathological processes. This comprehensive review delineates the significant insights into agmatine's pharmacological profile, emphasizing its structure and metabolism, neurotransmission and regulation, and pharmacokinetics and function. Agmatine's biosynthesis is highly conserved across species, highlighting its fundamental role in cellular functions. In the brain, comparable to established neurotransmitters, agmatine acts as a neuromodulator, influencing the regulation, metabolism, and reabsorption of neurotransmitters that are key to mood disorders, learning, cognition, and the management of anxiety and depression. Beyond its neuromodulatory functions, agmatine exhibits protective effects across various cellular and systemic contexts, including neuroprotection, nephroprotection, cardioprotection, and cytoprotection, suggesting a broad therapeutic potential. The review explores agmatine's interaction with multiple receptor systems, including NMDA, α2-adrenoceptors, and imidazoline receptors, elucidating its role in enhancing cell viability, neuronal protection, and synaptic plasticity. Such interactions underpin agmatine's potential in treating neurological diseases and mood disorders, among other conditions. Furthermore, agmatine's pharmacokinetics, including its absorption, distribution, metabolism, and excretion, are discussed, underlining the complexity of its action and the potential for therapeutic application. The safety and efficacy of agmatine supplementation, demonstrated through various animal and human studies, affirm its potential as a beneficial therapeutic agent. Conclusively, the diverse physiological and therapeutic effects of agmatine, spanning neurotransmission, protection against cellular damage, and modulation of various receptor pathways, position it as a promising candidate for further research and clinical application. This review underscores the imperative for continued exploration into agmatine's mechanisms of action and its potential in pharmacology and medicine, promising advances in the treatment of numerous conditions.

Effects of a dietary isoquinoline alkaloids blend on gut antioxidant capacity and gut barrier of young broilers.

Extensive mechanistic evidence to support the beneficial function of dietary phytobiotic applications for broiler performance, gut function and health is highly warranted. In particular, for isoquinoline alkaloids (IQ) the underlying mechanisms related to critical gut homeostasis components such as cytoprotection and gut barrier are scarce, especially for young broilers at the starter growth stage (d1-10). The aim of this study was to investigate the effect of a standardized blend of IQs on the relative gene expression of critical biomarkers relevant for antioxidant response and barrier function along the intestine of young broilers at the end of starter growth phase. For this purpose, 182 one-day-old Ross 308 broilers were allocated in 2 treatments with 7 replicates of 13 broilers each: control diet-no other additions (NC), and control diet containing a standardized blend of IQs at 200 mg/kg of diet (M) for the starter growth period (1-10d). The results revealed that the IQs blend significantly upregulated (P < 0.05) the expression of genes related to antioxidant response in all intestinal segments. Moreover, the IQs blend enhanced (P < 0.05) gut barrier components primarily at duodenal level. In conclusion, the blend of IQs beneficially affected critical pathway components relevant for the gut antioxidant capacity and barrier along the intestine of young broilers.

The Antioxidant, Antibacterial and Cell-Protective Properties of Bioactive Compounds Extracted from Rowanberry (Sorbus aucuparia L.) Fruits In Vitro.

Considering that Sorbus aucuparia fruits have been underutilized despite their tremendous potential, this study aimed to correlate the in vitro antioxidant, antibacterial and cell-protective abilities of fruit extracts derived from Sorbus aucuparia Romanian cultivars with their phytochemical composition. Therefore, following the preparation of ethanolic and carotenoid extracts, phytochemical screening was performed using UV-Vis and HPLC-DAD-ESI-MS methods. The antioxidant activity was analyzed using DPPH and FRAP tests. As the results revealed high contents of bioactive compounds (polyphenols 1.11 mg GAE/g DM, flavonoids 430.06 µg QE/g DM and carotenoids 95.68 µg/g DM) and an important antiradical action (DPPH 24.51 mg/mL and FRAP 0.016 µM TE/mL), we chose to further examine the fruits' biological properties. The antibacterial capacity was assessed employing agar well diffusion and broth microdilution techniques, with fruits displaying an intense activity against MSSA, MRSA and Enterococcus faecalis, but also E. coli and Pseudomonas aeruginosa. The cell-protective activity was analyzed on gentamicin-stressed renal cells, through MTT and Annexin V-FITC assays. Importantly, a significant increase in viability was registered on stressed cells following extract administration in low doses; nevertheless, viability was noticed to decline when exposed to elevated concentrations, potentially due to the cumulative actions of the extract and gentamicin. These findings offer novel light on the antibacterial activity of Sorbus aucuparia Romanian cultivars, as well as their cell-protective ability in renal cell injury.

Disrupting the SKN-1 homeostat: mechanistic insights and phenotypic outcomes.

The mechanisms that govern maintenance of cellular homeostasis are crucial to the lifespan and healthspan of all living systems. As an organism ages, there is a gradual decline in cellular homeostasis that leads to senescence and death. As an organism lives into advanced age, the cells within will attempt to abate age-related decline by enhancing the activity of cellular stress pathways. The regulation of cellular stress responses by transcription factors SKN-1/Nrf2 is a well characterized pathway in which cellular stress, particularly xenobiotic stress, is abated by SKN-1/Nrf2-mediated transcriptional activation of the Phase II detoxification pathway. However, SKN-1/Nrf2 also regulates a multitude of other processes including development, pathogenic stress responses, proteostasis, and lipid metabolism. While this process is typically tightly regulated, constitutive activation of SKN-1/Nrf2 is detrimental to organismal health, this raises interesting questions surrounding the tradeoff between SKN-1/Nrf2 cryoprotection and cellular health and the ability of cells to deactivate stress response pathways post stress. Recent work has determined that transcriptional programs of SKN-1 can be redirected or suppressed to abate negative health outcomes of constitutive activation. Here we will detail the mechanisms by which SKN-1 is controlled, which are important for our understanding of SKN-1/Nrf2 cytoprotection across the lifespan.

Separation, enrichment and cytoprotection of antioxidant peptides from Xuanwei ham using aqueous two-phase extraction.

An ethanol/(NH4)2SO4 biphasic (aqueous two-phase) system was designed to effectively separate antioxidant peptides from Xuanwei ham, and its potential to prevent ultraviolet A-induced damage to skin cells was explored. Optimization via single factor experiments and response surface methodology revealed that under 20 % ethanol aqueous solution (w/w), 25.5 % (NH4)2SO4 aqueous solution (w/w), and pH 8.80 conditions, the optimal extraction ratio was 59.0 ± 1.73 %. In vitro antioxidant activity and cellular assays showed that the peptide purified in the upper phase exhibited strong antioxidant activity, increasing the viability of HaCat cells damaged by UVA irradiation from 56.14 ± 1.05 % to 66.3 ± 1.76 %. We used an in silico peptide screening strategy and identified 10 with potential antioxidant activity, emphasizing the important role of amino acids Pro, Gly, and Ala in antioxidant activity.

Cytoprotective role of human dental pulp stem cell-conditioned medium in chemotherapy-induced alopecia.

BACKGROUND: Chemotherapy-induced alopecia (CIA) is a distressing adverse effect of chemotherapy, with an estimated incidence of 65% and limited treatment options. Cyclophosphamide (CYP) is a common alopecia-inducing chemotherapy agent. Human dental pulp stem cells (DPSCs) secrete several paracrine factors that up-regulate hair growth. Conditioned medium (CM) collected from DPSCs (DPSC-CM) promotes hair growth; culturing mesenchymal stem cells under hypoxic conditions can enhance this effect. METHODS: The effect of DPSC-CM cultured under normoxic (N-) and hypoxic (H-) conditions against CYP-mediated cytotoxicity in keratinocytes was examined using cell viability assay, lactate dehydrogenase (LDH) cytotoxicity assay, and apoptosis detection. The damage-response pathway was determined in a well-established CIA mouse model by analyzing macroscopic effects, histology, and apoptosis. Reverse transcription-quantitative PCR and Caspase-3/7 activity assay were used to investigate the impact of DPSC-CM on the molecular damage-response pathways in CYP-treated mice. The effect of post-CIA DPSC-CM application on post-CIA hair regrowth was analyzed by macroscopic effects and microstructure observation of the hair surface. Furthermore, to investigate the safety of DPSC-CM as a viable treatment option, the effect of DPSC-CM on carcinoma cell lines was examined by cell viability assay and a subcutaneous tumor model. RESULTS: In the cell viability assay, DPSC-CM was observed to increase the number of keratinocytes over varying CYP concentrations. Furthermore, it reduced the LDH activity level and suppressed apoptosis in CYP-treated keratinocytes. DPSC-CM exhibited the cytoprotective role in vivo via the dystrophic anagen damage-response pathway. While both N-CM and H-CM downregulated the Caspase-3/7 activity level, H-CM downregulated Caspase-3 mRNA expression. The proportion of post-CIA H-CM-treated mice with > 90% normal hair was nearly twice that of vehicle- or N-CM-treated mice between days 50 and 59 post-depilation, suggesting that post-CIA H-CM application may accelerate hair regrowth and improve hair quality. Furthermore, DPSC-CM suppressed proliferation in vitro in certain carcinoma cell lines and did not promote the squamous cell carcinoma (SCC-VII) tumor growth rate in mice. CONCLUSIONS: The potentiality of DPSC-CM and H-CM as a promising cytoprotective agent and hair regrowth stimulant, respectively, for CIA needs in-depth exploration.

Rationale and design of Treatment of Acute Ischaemic Stroke with Edaravone Dexborneol II (TASTE-2): a multicentre randomised controlled trial.

BACKGROUND: Edaravone dexborneol is believed to be a novel cytoprotective drug, demonstrating a synergistic combination of antioxidative and anti-inflammatory properties in animal models. The Treatment of Acute Ischaemic Stroke with Edaravone Dexborneol (TASTE) trial demonstrated its superior efficacy over edaravone alone for acute ischaemic stroke (AIS) patients. However, its efficacy in individuals undergoing endovascular therapy (EVT) remains uncertain. AIM: To clarify the rationale and design of the TASTE II (TASTE-2) trial. DESIGN: The TASTE-2 is a multicentre, double-blind, randomised, placebo-controlled trial designed to evaluate the efficacy and safety of edaravone dexborneol in patients with AIS and large-vessel occlusion in the anterior circulation. The eligible participants, presenting with a National Institute of Health Stroke Scale score between 6 and 25 (range 0-42, with larger values suggesting severe neurological dysfunction) and an Alberta Stroke Program Early Computed Tomography Score ranging from 6 to 10 (range 0-10, with smaller values suggesting larger infarction) within the initial 24 hours after symptom onset, will be randomly allocated to either the edaravone dexborneol group or the placebo group in equal proportions prior to thrombectomy. The treatment will be continuously administered for a duration of 10-14 days. A follow-up period of 90 days will be implemented for all participants. STUDY OUTCOMES: The primary efficacy outcome is defined as achieving favourable functional independence, measured by a modified Rankin Scale of 0-2 at 90 days. The primary safety outcome focuses on the incidence of serious adverse events. DISCUSSION: The TASTE-2 trial will provide evidence to determine whether the administration of edaravone dexborneol in AIS patients undergoing EVT could yield significant improvements in neurological function.

Cationic Vitamin E-TPGS Mixed Micelles of Berberine to Neutralize Doxorubicin-Induced Cardiotoxicity via Amelioration of Mitochondrial Dysfunction and Impeding Apoptosis.

Anthracycline antibiotics, namely, doxorubicin (DOX) and daunorubicin, are among the most widely used anticancer therapies, yet are notoriously associated with severe myocardial damage due to oxidative stress and mitochondrial damage. Studies have indicated the strong pharmacological properties of Berberine (Brb) alkaloid, predominantly mediated via mitochondrial functions and nuclear networks. Despite the recent emphasis on Brb in clinical cardioprotective studies, pharmaceutical limitations hamper its clinical use. A nanoformulation for Brb was developed (mMic), incorporating a cationic lipid, oleylamine (OA), into the TPGS-mixed corona of PEGylated-phosphatidylethanolamine (PEG-PE) micelles. Cationic TPGS/PEG-PE mMic with superior Brb loading and stability markedly enhanced both intracellular and mitochondria-tropic Brb activities in cardiovascular muscle cells. Sub-lethal doses of Brb via cationic OA/TPGS mMic, as a DOX co-treatment, resulted in significant mitochondrial apoptosis suppression. In combination with an intense DOX challenge (up to ~50 µM), mitochondria-protective Brb-OA/TPGS mMic showed a significant 24 h recovery of cell viability (p ≤ 0.05-0.01). Mechanistically, the significant relative reduction in apoptotic caspase-9 and elevation of antiapoptotic Bcl-2 seem to mediate the cardioprotective role of Brb-OA/TPGS mMic against DOX. Our report aims to demonstrate the great potential of cationic OA/TPGS-mMic to selectively enhance the protective mitohormetic effect of Brb to mitigate DOX cardiotoxicity.

Therapeutic Effects of Stimulating the Melanocortin Pathway in Regulating Ocular Inflammation and Cell Death.

Alpha-melanocyte-stimulating hormone (α-MSH) and its binding receptors (the melanocortin receptors) play important roles in maintaining ocular tissue integrity and immune homeostasis. Particularly extensive studies have demonstrated the biological functions of α-MSH in both immunoregulation and cyto-protection. This review summarizes the current knowledge of both the physiological and pathological roles of α-MSH and its receptors in the eye. We focus on recent developments in the biology of α-MSH and the relevant clinical implications in treating ocular diseases.

Improved Efficacy of Delayed Treatment with Human Bone Marrow-Derived Stromal Cells Evaluated in Rats with Spinal Cord Injury.

The treatment of spinal cord injury (SCI) with uncultivated human bone marrow-derived stromal cells (bmSCs) prepared by negative selection has been proposed to be therapeutically superior to treatment with stem cells that were expanded in vitro. To explore their use in clinical trials, we studied the functional effects of delayed application at 7 days after SCI by testing different doses of bmSCs. Spinal cord contusion injury was induced in adult male Wistar rats at the thoracic level T9. Human bmSCs were prepared by negative selection without expansion in vitro (NeuroCellsTM). Treatment consisted of one 150 µL injection into the cisterna magna containing 0.5 or 2.5 million fresh bmSCs or 2.5 million bmSCs. The recovery of motor functions was evaluated during a surveillance period of six weeks (6 W), during which spinal cords were assessed histologically. Treatment resulted in a significant, dose-dependent therapeutic effect on the recovery of motor performance. The histological analysis revealed a lower degree of axonal degeneration and better survival of neurons and oligodendrocytes in bmSCs treated rats. Our results support delayed intrathecal application of bmSCs prepared by negative selection without expansion in vitro as a treatment of SCI.

Hydrogen sulfide (H2S) metabolism: Unraveling cellular regulation, disease implications, and therapeutic prospects for precision medicine.

Hydrogen sulfide (H2S), traditionally recognized as a noxious gas with a pungent odor, has emerged as a fascinating metabolite originating from proteinaceous foods. This review provides a comprehensive examination of H2S regulatory metabolism in cell. Dysregulation of cellular processes plays a pivotal role in the pathogenesis of numerous diseases. Recent development explores the chemistry of biosynthesis and degradation of H2S in cells. The consequences of dysregulation causing diseases and the emerging role of hydrogen sulfide (H2S) modulation as a promising therapeutic platform has not been explored much. These disturbances can manifest as oxidative stress, inflammation, and aberrant cellular signaling pathways, contributing to the development and progression of diseases such as cancer, cardiovascular disorders, neurodegenerative diseases, and diabetes. Hydrogen sulfide has gained recognition as a key player in cellular regulation. H2S is involved in numerous physiological processes, including vasodilation, inflammation control, and cytoprotection. Recent advances in research have focused on modulating H2S levels to restore cellular balance and mitigate disease progression. This approach involves both exogenous H2S donors and inhibitors of H2S -producing enzymes. By harnessing the versatile properties of H2S, researchers and clinicians may develop innovative therapies that address the root causes of dysregulation-induced diseases. As our understanding of H2S biology deepens, the potential for precision medicine approaches tailored to specific diseases becomes increasingly exciting, holding the promise of improved patient outcomes and a new era in therapeutics.

Oleander attenuates hepatic inflammation in a TLR4-independent manner and by favorable modulation of hepatocellular global metabolome that supports cytoprotection.

ETHNOPHARMACOLOGICAL RELEVANCE: Nerium oleander is used to treat liver-associated chronic metabolic diseases in traditional medicinal systems across the globe. The hepatoprotective effects of oleander are mentioned in Indian and Chinese traditional medicinal literature. AIM OF THE STUDY: The present study aimed to investigate the cellular mechanisms behind the hepatoprotective effects of a non-toxic dose of oleander (NO). MATERIALS AND METHODS: The hepatoprotective effects of NO were tested against lipopolysaccharide (LPS)-treated HepG2 cells. Oxidative stress response was studied using cellular enzymatic assays, and gene expression was analyzed using qRT-PCR. HepG2 cells were pretreated with TAK-242 (pharmacological inhibitor of TLR4) to decipher the anti-inflammatory mechanisms of NO. Cell-free metabolites were analyzed using GCMS and were subjected to pathway enrichment analysis. RESULTS: NO reduced systemic inflammation, serum lipid peroxidation byproducts, and glucose without affecting serum transaminase levels and hepatic histopathological features. NO attenuated the inflammation-induced loss of antioxidant enzyme activities and mRNA expressions of toll-like receptor-4 (TLR4)/nuclear factor κß (NFκß)-dependent inflammatory genes. In TAK-242 pretreated cells, LPS was unable to induce inflammatory and oxidative responses. However, NO treatment in TAK-242 pretreated cells with LPS stimulation further reduced the signs of inflammation and improved hepatoprotective activities. A comparative analysis of the intracellular global metabolome from HepG2 cells with and without NO treatment indicated NO-mediated favorable modulation of intracellular metabolic pathways that support cytoprotective activities. CONCLUSION: NO protects HepG2 cells from LPS-induced oxidative and inflammatory injury. The hepatoprotective effects of NO are mediated by a TLR4-independent process and through a favorable modulation of the intracellular global metabolome that supports cytoprotection.

MicroRNA-10a enrichment in factor VIIa-released endothelial extracellular vesicles: potential mechanisms.

BACKGROUND: Factor VIIa induces the release of extracellular vesicles (EVs) from endothelial cells (EEVs). Factor VIIa-released EEVs are enriched with microRNA-10a (miR10a) and elicit miR10a-dependent cytoprotective responses. OBJECTIVES: To investigate mechanisms by which FVIIa induces miR10a expression in endothelial cells and sorts miR10a into the EVs. METHODS: Activation of Elk-1 and TWIST1 expression was analyzed by immunofluorescence microscopy and immunoblot analysis. Small interfering RNA silencing approach was used to knock down the expression of specific genes in endothelial cells. EVs secreted from endothelial cells or released into circulation in mice were isolated by centrifugation and quantified by nanoparticle tracking analysis. Factor VIIa or EVs were injected into mice; mice were challenged with lipopolysaccharides to assess the cytoprotective effects of FVIIa or EVs. RESULTS: FVIIa activation of ERK1/2 triggered the activation of Elk-1, which led to the induction of TWIST1, a key transcription factor involved in miR10a expression. Factor VIIa also induced the expression of La, a small RNA-binding protein. Factor VIIa-driven acid sphingomyelinase (ASM) activation and the subsequent activation of the S1P receptor pathway were responsible for the induction of La. Silencing of ASM or La significantly reduced miR10a levels in FVIIa-released EEVs without affecting the cellular expression of miR10a. Factor VIIa-EEVs from ASM knocked-down cells failed to provide cytoprotective responses in cell and murine model systems. Administration of FVIIa protected wild-type but not ASM-/- mice against lipopolysaccharide-induced inflammation and vascular leakage. CONCLUSION: Our data suggest that enhanced cellular expression of miR10a coupled with La-dependent sorting of miR10a is responsible for enriching FVIIa-released EVs with miR10a.

Byrsonima sericea Ethanol Extract Protected PC12 Cells from the Oxidative Stress and Apoptosis Induced by 6-Hydroxydopamine.

Parkinson's disease is characterized by the progressive loss of dopaminergic neurons in the nigrostriatal pathway and oxidative stress is one of the main mechanisms that lead to neuronal death in this disease. Previous studies have shown antioxidant activity from the leaves of Byrsonima sericea, a plant of the Malpighiaceae family. This study aimed to evaluate the cytoprotective activity of the B. sericea ethanolic extract (BSEE) against the cytotoxicity induced by 6-hydroxydopamine (6-OHDA) in PC12 cells, an in vitro model of parkinsonism. The identification of phenolic compounds in the extract by HPLC-DAD revealed the presence of geraniin, rutin, isoquercetin, kaempferol 3-O-ß-rutinoside, and quercetin. The BSEE (75-300 µg/mL) protected PC12 cells from toxicity induced by 6-OHDA (25 µg/mL), protected cell membrane integrity and showed antioxidant activity. BSEE was able to decrease nitrite levels, glutathione depletion, and protect cells from 6-OHDA-induced apoptosis. Thus, we suggest that the BSEE can be explored as a possible cytoprotective agent for Parkinson's disease due to its high antioxidant capacity and anti-apoptotic action.

Protective effects of fruit extract of Rosa canina and quercetin on human umbilical vein endothelial cell injury induced by hydrogen peroxide.

The Nastaran plant, with the scientific name of Rosa canina, has been used since ancient times as a plant with medicinal properties. In the present study, human umbilical vein endothelial cells (HUVECs) were used to examine the protective effects of R. canina fruit extract (RCFE) and its flavonoid ingredient (quercetin) against H2O2-induced cell injury. RCFE (1.25-20 µg/mL) and quercetin (1.25-20 µM) were exposed to H2O2-oxidizing agent (1 and 2 mM) and the protective effect was examined on HUVEC cells by Alamar Blue test. The amount of intracellular reactive oxygen species (ROS) was measured by using DCFDA reagent by fluorimetric method. The effects of RCFE and quercetin on cell apoptosis were studied by staining with hypotonic PI solution and flow cytometry. The amount of PARP and survivin involved in the apoptotic process was measured using the western blot analysis. The results of the Alamar Blue test showed that RCFE and quercetin could reduce the toxicity of H2O2. RCFE and quercetin were able to significantly increase cell viability against H2O2. Also, it was found that RCFE and quercetin reduced the production of ROS by H2O2. It was found that RCFE and quercetin reduced the apoptosis and sub-G1 peak area in flow histogram after exposure of cells to H2O2. Based on western blot results, pretreatment with RCFE and quercetin could significantly increase survivin protein after exposure of cells to H2O2. Also, RCFE and quercetin could significantly reduce the amount of cleaved PARP after exposure of cells to H2O2. RCFE and its ingredient (quercetin) can be considered a promising source of phytochemicals in the prevention of cardiovascular diseases.

Stress-free cell aggregation by using the CEPT cocktail enhances embryoid body and organoid fitness.

Embryoid bodies (EBs) and self-organizing organoids derived from human pluripotent stem cells (hPSCs) recapitulate tissue development in a dish and hold great promise for disease modeling and drug development. However, current protocols are hampered by cellular stress and apoptosis during cell aggregation, resulting in variability and impaired cell differentiation. Here, we demonstrate that EBs and various organoid models (e.g., brain, gut, kidney) can be optimized by using the small molecule cocktail named CEPT (chroman 1, emricasan, polyamines, trans-ISRIB), a polypharmacological approach that ensures cytoprotection and cell survival. Application of CEPT for just 24 h during cell aggregation has long-lasting consequences affecting morphogenesis, gene expression, cellular differentiation, and organoid function. Various qualification methods confirmed that CEPT treatment enhanced experimental reproducibility and consistently improved EB and organoid fitness as compared to the widely used ROCK inhibitor Y-27632. Collectively, we discovered that stress-free cell aggregation and superior cell survival in the presence of CEPT are critical quality control determinants that establish a robust foundation for bioengineering complex tissue and organ models.

The N-end rule pathway regulates ER stress-induced clusterin release to the cytosol where it directs misfolded proteins for degradation.

Previous work suggests that cell stress induces release of the normally secreted chaperone clusterin (CLU) into the cytosol. We analyzed the localization of CLU in healthy and stressed cells, the mechanism of its cytosolic release, and its interactions with cytosolic misfolded proteins. Key results of this study are the following: (1) full-length CLU is released to the cytosol during stress, (2) the CLU N-terminal D1 residue is recognized by the N-end rule pathway and together with the enzyme ATE1 is essential for cytosolic release, (3) CLU can form stable complexes with cytosolic misfolded proteins and direct them to the proteasome and autophagosomes, and (4) cytosolic CLU protects cells from hypoxic stress and the cytosolic overexpression of an aggregation-prone protein. Collectively, the results suggest that enhanced cytosolic release of CLU is a stress response that can inhibit the toxicity of misfolded proteins and facilitate their targeted degradation via both autophagy and the proteasome.

[Cultured Cells in the Aging Research, Exhibiting Cell Surface Component Functions, Intracellular Signaling, a Novel Adaptor Molecule, Aging Phenotype Expression and Various Aspects of the Cellular Physiology].

Cellular aging is one of the most extraordinary phenomena that mammalian cells undergo in vivo and in vitro. We have been observing their behavior for approximately 4 decades and here would like to summarize some of our salient findings. Normal cells such as human diploid cells exhibit finite growth potential in vitro as well as a set of senescent cell phenotypes. Those changes appear probabilistic and irreversible. In the search of the factor(s) to evoke the features we have observed that cellular glycosaminoglycan molecules plays significant roles in the cell physiology. Besides, CCAAT-box binding transcription factor NF-Y relates to the aging-coupled changes in gene expression, and aging of gastric mucosal cells may relate to a decrease in cytoprotection. As to the intracellular signaling, we have confirmed that the breakdown of phosphatidylinositol bisphosphate is critical for mitogenesis by using micro-injection of its antibody. Subsequently, we have discovered a novel, pivotal adaptor protein Grb2/Ash, a missing link between the receptor tyrosine kinases and their downstream target Ras. The limiting factors for the cellular life span have been considered as telomere shortening and accumulation of cellular and genomic damages. We have observed that telomerase-expressing cells exhibit expanded division potential; yet oxidative stress similarly induces senescent cell phenotypes. Herein we have demonstrated that the treatment of senescent cells with nicotinamide or related reagents elicits unique cellular responses, which might indicate the capability of the cells to recover from the aging.

Synthesis of Bis-Chalcones and Evaluation of Its Effect on Peroxide-Induced Cell Death and Lipopolysaccharide-Induced Cytokine Production.

Plant secondary metabolites are important sources of biologically active compounds with wide pharmacological potentials. Among the different classes, the chalcones form integral pharmacologically active agents. Natural chalcones and bis-chalcones exhibit high antioxidant and anti-inflammatory properties in various experiments. Studies are also underway to explore more biologically active bis-chalcones by chemical synthesis of these compounds. In this study, the effects of six synthetic bis-chalcones were evaluated in intestinal epithelial cells (IEC-6); further, the anti-inflammatory potentials were studied in lipopolysaccharide-induced cytokine production in macrophages. The synthesized bis-chalcones differ from each other first of all by the nature of the aromatic cores (functional group substitution, and their position) and by the size of a central alicycle. The exposure of IEC-6 cells to peroxide radicals reduced the cell viability; however, pre-treatment with the bis-chalcones improved the cell viability in these cells. The mechanism of action was observed to be the increased levels of glutathione and antioxidant enzyme activities. Further, these bis-chalcones also inhibited the LPS-stimulation-induced inflammatory cytokine production in RAW 264.7 macrophages. Overall, the present study indicated the cytoprotective and anti-inflammatory abilities of synthetic bis-chalcones.