Correction: Inhibition of the Growth Factor MDK/Midkine by a Novel Small Molecule Compound to Treat Non-Small Cell Lung Cancer.

[This corrects the article DOI: 10.1371/journal.pone.0071093.].

The Uptake of Heparanase into Mast Cells Is Regulated by Its Enzymatic Activity to Degrade Heparan Sulfate.

Mast cells take up extracellular latent heparanase and store it in secretory granules. The present study examined whether the enzymatic activity of heparanase regulates its uptake efficiency. Recombinant mouse heparanase mimicking both the latent and mature forms (L-Hpse and M-Hpse, respectively) was internalized into mastocytoma MST cells, peritoneal cell-derived mast cells, and bone marrow-derived mast cells. The internalized amount of L-Hpse was significantly higher than that of M-Hpse. In MST cells, L-Hpse was continuously internalized for up to 8 h, while the uptake of M-Hpse was saturated after 2 h of incubation. L-Hpse and M-Hpse are similarly bound to the MST cell surface. The expression level of cell surface heparan sulfate was reduced in MST cells incubated with M-Hpse. The internalized amount of M-Hpse into mast cells was significantly increased in the presence of heparastatin (SF4), a small molecule heparanase inhibitor that does not affect the binding of heparanase to immobilized heparin. Enzymatically quiescent M-Hpse was prepared with a point mutation at Glu335. The internalized amount of mutated M-Hpse was significantly higher than that of wild-type M-Hpse but similar to that of wild-type and mutated L-Hpse. These results suggest that the enzymatic activity of heparanase negatively regulates the mast cell-mediated uptake of heparanase, possibly via the downregulation of cell surface heparan sulfate expression.

Suppression of angiotensin converting enzyme 2, a host receptor for SARS-CoV-2 infection, using 5-aminolevulinic acid in vitro.

Angiotensin converting enzyme 2 (ACE2), an entry receptor found on the surface of host cells, is believed to be detrimental to the infectious capability of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Scientists have been working on finding a cure since its outbreak with limited success. In this study, we evaluated the potential of 5-aminolevulinic acid hydrochloride (ALA) in suppressing ACE2 expression of host cells. ACE2 expression and the production of intracellular porphyrins following ALA administration were carried out. We observed the reduction of ACE2 expression and intracellular porphyrins following ALA administration. ALA suppressed the ACE2 expression in host cells which might prevent binding of SARS-CoV-2 to host cells. Co-administration of ALA and sodium ferrous citrate (SFC) resulted in a further decrease in ACE2 expression and increase in intracellular heme level. This suggests that the suppression of ACE2 expression by ALA might occur through heme production. We found that the inhibition of heme oxygenase-1 (HO-1), which is involved in heme degradation, also resulted in decrease in ACE2 expression, suggesting a potential role of HO-1 in suppressing ACE2 as well. In conclusion, we speculate that ALA, together with SFC administration, might serve as a potential therapeutic approach in reducing SARS-CoV-2 infectivity through suppression of ACE2 expression.

A Randomized Phase 2 Study of 5-Aminolevulinic Acid Hydrochloride and Sodium Ferrous Citrate for the Prevention of Nephrotoxicity Induced by Cisplatin-Based Chemotherapy of Lung Cancer.

INTRODUCTION: Cisplatin-based chemotherapy was established in the 1980s, and it has been improved by the development of a short hydration protocol in lung cancer therapy. However, cisplatin-based chemotherapy is still associated with renal toxicity. Because 5-aminolevulinic acid (5-ALA) with sodium ferrous citrate (SFC) is known to be a mitochondrial activator and a heme oxygenase-1 (HO-1) inducer, 5-ALA with SFC is speculated to mitigate cisplatin-induced renal inflammation. METHODS: We investigated the effects of oral administration of 5-ALA with SFC for preventing cisplatin-based nephrotoxicity in patients with lung cancer and evaluated its benefits for patients who received cisplatin-based chemotherapy. The primary endpoint was the significance of the difference between the serum creatinine (sCr) levels of the patients administered 5-ALA with SFC and those given placebo after course 1 of chemotherapy. The difference in the estimated glomerular filtration rate (eGFR) between the two groups was also evaluated as the secondary endpoint. RESULTS: The double-blind, randomized two-arm studies were conducted at 15 medical facilities in Japan; 54 male and 20 female patients with lung cancer who received cisplatin-based chemotherapy between the ages of 42 and 75 years were included in the study. The compliance rate was greater than 94% in the primary assessment and subsequent drug administration periods. All enrolled patients completed the four cycles of cisplatin-based chemotherapy with short hydration. The average level of sCr on day 22 of course 1 was 0.707 mg/dL in the group treated with 5-ALA and SFC and 0.735 mg/dL in the placebo group, respectively, and the sCr in the test group was significantly lower than that in the placebo group (p = 0.038). In addition, the eGFR was significantly higher in the SPP-003 group than in the placebo group up to day 1 of course 3 (84.66 and 75.68 mL/min/1.73 m2, respectively, p = 0.02) and kept better even after the last administration of the study drug (82.37 and 73.49 mL/min/1.73 m2, respectively, p = 0.013). CONCLUSIONS: The oral administration of 5-ALA with SFC is beneficial to patients undergoing cisplatin-based chemotherapy for lung cancer with short hydration.

Sulfated Hyaluronan Binds to Heparanase and Blocks Its Enzymatic and Cellular Actions in Carcinoma Cells.

We examined whether sulfated hyaluronan exerts inhibitory effects on enzymatic and biological actions of heparanase, a sole endo-beta-glucuronidase implicated in cancer malignancy and inflammation. Degradation of heparan sulfate by human and mouse heparanase was inhibited by sulfated hyaluronan. In particular, high-sulfated hyaluronan modified with approximately 2.5 sulfate groups per disaccharide unit effectively inhibited the enzymatic activity at a lower concentration than heparin. Human and mouse heparanase bound to immobilized sulfated hyaluronan. Invasion of heparanase-positive colon-26 cells and 4T1 cells under 3D culture conditions was significantly suppressed in the presence of high-sulfated hyaluronan. Heparanase-induced release of CCL2 from colon-26 cells was suppressed in the presence of sulfated hyaluronan via blocking of cell surface binding and subsequent intracellular NF-κB-dependent signaling. The inhibitory effect of sulfated hyaluronan is likely due to competitive binding to the heparanase molecule, which antagonizes the heparanase-substrate interaction. Fragment molecular orbital calculation revealed a strong binding of sulfated hyaluronan tetrasaccharide to the heparanase molecule based on electrostatic interactions, particularly characterized by interactions of (-1)- and (-2)-positioned sulfated sugar residues with basic amino acid residues composing the heparin-binding domain-1 of heparanase. These results propose a relevance for sulfated hyaluronan in the blocking of heparanase-mediated enzymatic and cellular actions.

Tranilast as an Adjunctive Therapy in Hospitalized Patients with Severe COVID- 19: A Randomized Controlled Trial.

BACKGROUND: Tranilast is a potential NLRP3 inflammasome inhibitor that may relieve progressive inflammation due to COVID-19. AIM OF THE STUDY: To evaluate the therapeutic effects of Tranilast in combination with antiviral drugs in non-ICU-admitted hospitalized patients with COVID-19. METHODS: This study was an open-label clinical trial that included 72 hospitals admitted patients with severe COVID-19 at Razi Hospital, Ahvaz, Iran, from July 2020-August 2020. These patients were randomly assigned in a 1:1 ratio to control (30) and intervention groups (30). Patients in the control group received antiviral therapy, while patients in the intervention group received Tranilast (300 mg daily) in addition to the antiviral drugs for Seven days. The collected data, including the expression of inflammatory cytokine, laboratory tests, and clinical findings, was used for intragroup comparisons. RESULTS: The intervention group showed significantly lower levels of NLR (p = 0.001), q-CRP (p = 0.002), IL-1 (p = 0.001), TNF (p = 0.001), and LDH (p = 0.046) in comparison with the control group. The effect of intervention was significant in increasing the o2 saturation (F = 7.72, p = 0.007). Long hospitalization (four days or above) was 36.6% in the Tranilast and 66.6% in the control group (RR = 0.58; 95% CI: 0.38-1.06, p = 0.045). In the Tranilst and control groups, one and four deaths or hospitalization in ICU were observed respectively (RR = 0.31; 95% CI: 0.03-2.88, p = 0.20). CONCLUSIONS: Tranilast might be used as an effective and safe adjuvant therapy and enhance the antiviral therapy's efficacy for managing patients with COVID-19.

Efficacy and Safety of 5-Aminolevulinic Acid for Patients with Symptoms of Late-Onset Hypogonadism: A Preliminary Study.

PURPOSE: As the concept of late-onset hypogonadism (LOH) has gained increased attention, the treatment of eugonadal patients with LOH symptom has become a clinical problem. Previous studies have shown the possible benefits of 5-aminolevulinic acid (5-ALA) on the somatic, psychological and sexual functions. We therefore conducted this randomized, double-blind, placebo-controlled study to confirm the efficacy and safety of 5-ALA for LOH symptoms. MATERIALS AND METHODS: Thirty-two eugonadal subjects with LOH symptoms were randomly divided into a 5-ALA group (n=15) and a placebo group (n=17). Treatment was continued for 8 weeks. The change of the Aging Males' Symptoms (AMS) scale score and several biochemical and endocrinological variables during treatment were compared between the groups. RESULTS: After treatment, the change in the total AMS in the 5-ALA group was significantly greater than that in the placebo group (-7.4±4.7 vs. -4.9±4.9, p=0.029). However, the differences between the groups in the change of the somatic, psychological, and sexual sub-scores of the AMS did not reach the statistical significance, although these changes in the 5-ALA group were greater than those in the placebo group. Furthermore, the change in the biochemical and endocrinological variables in the two groups did not differ to a statistically significant extent. During the 8-week treatment period, no patients discontinued 5-ALA due to treatment-emergent adverse events (TEAEs). CONCLUSIONS: The intake of 5-ALA for 8 weeks was beneficial for eugonadal patients with symptoms of LOH and no severe TEAEs was experienced. 5-ALA should be considered as an option for those patients.

Effect of 5-aminolevulinic acid on gene expression and presence of NKG2D receptor on NK cells.

Natural killer (NK) cells are involved in innate and acquired immunity, stimulating and enhancing immune responses via secretion of IFN-γ and TNF-α. NKG2D is among the most important NK's stimulant receptors, the ligands of which are elevated on cancerous and virus-infected cells. We analyzed effect of 5-ALA on gene expression and receptor presentation of NKG2D, which is present on peripheral blood NK cells. Mononuclear cells were isolated from the venous blood samples of healthy individuals. RNA extraction and cDNA synthesis were performed after exposure of samples to 5-ALA, and gene expression was evaluated using Real-Time PCR, and the receptor presence rate on the cell surface was evaluated by flow-cytometry analysis. The results showed the gene expression of NKG2D and the presence of its receptor on NK cells were increased.5-ALA can be used to activate NK cells in their killing activity, preventing the growth and metastasis of cancerous cells.

5-Aminolevulinic acid/sodium ferrous citrate enhanced the antitumor effects of programmed cell death-ligand 1 blockade by regulation of exhausted T cell metabolism in a melanoma model.

Mitochondria are key cytoplasmic organelles. Their activation is critical for the generation of T cell proliferation and cytotoxicity. Exhausted tumor-infiltrating T cells show a decreased mitochondrial function and mass. 5-Aminolevulinic acid (5-ALA), a natural amino acid that is only produced in the mitochondria, has been shown to influence metabolic functions. We hypothesized that 5-ALA with sodium ferrous citrate (SFC) might provide metabolic support for tumor-infiltrating T cells. In a mouse melanoma model, we found that 5-ALA/SFC with a programmed cell death-ligand 1 (PD-L1) blocking Ab synergized tumor regression. After treatment with 5-ALA/SFC and anti-PD-L1 Ab, tumor infiltrating lymphocytes (TILs) were not only competent for the production of cytolytic particles and cytokines (granzyme B, interleukin-2, and γ-interferon) but also showed enhanced Ki-67 activity (a proliferation marker). The number of activated T cells (PD-1+ Tim-3- ) was also significantly increased. Furthermore, we found that 5-ALA/SFC activated the mitochondrial functions, including the oxygen consumption rate, ATP level, and complex V expression. The mRNA levels of Nrf-2, HO-1, Sirt-1, and PGC-1α and the protein levels of Sirt-1 were upregulated by treatment with 5-ALA/SFC. Taken together, our findings revealed that 5-ALA/SFC could be a key metabolic regulator in exhausted T cell metabolism and suggested that 5-ALA/SFC might synergize with anti-PD-1/PD-L1 therapy to boost the intratumoral efficacy of tumor-specific T cells. Our study not only revealed a new aspect of immune metabolism, but also paved the way to develop a strategy for combined anti-PD-1/PD-L1 cancer immunotherapy.

Efficiency of aminolevulinic acid (ALA)-photodynamic therapy based on ALA uptake transporters in a cell density-dependent malignancy model.

The effectiveness of the conventional chemotherapy for cancer are compromised as the cancer cells advances in their malignancy level as they acquired drug resistance. In this study, we aimed to evaluate the efficiency of aminolevulinic acid-photodynamic therapy (ALA-PDT) against cancer of various malignancy levels, indicated by the expression level of receptor associated nuclear factor-κB ligand (RANKL), through the expression levels of ALA uptake transporters. We established a malignancy model by gradually increasing the cell density of cancer cells. Western blotting was used to study the expression levels of RANKL, ALA uptake transporters and the cell density-dependent Yes-associated protein (YAP) under different cell densities. The amount of protoporphyrin (PpIX) produced and cell viability were then studied using high performance liquid chromatography (HPLC) and ALA-PDT assay. Our study showed that the amount of PpIX production doubled in high cell density/cancer malignancy cultures and the effectiveness of ALA-PDT when subjected to light irradiation at 635 nm are significantly at higher cancer malignancy. We observed that the expression levels of ALA uptake transporters and YAP correlated with higher cell density/cancer malignancy, suggesting a possible relationship among these three factors. These findings suggest that ALA-PDT is more effective in cancer cells of higher malignancy due to the upregulation of transporters involved in ALA uptake.

5-aminolevulinic acid combined with sodium ferrous citrate ameliorated lupus nephritis in a mouse chronic graft-versus-host disease model.

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the abnormal activation of immune cells and hypersecretion of autoantibodies and causes irreversible chronic damage, such as lupus nephritis. Chronic graft-versus-host-disease (cGvHD) in mice induced by the injection of parental mouse lymphocytes into F1 hybrids leads to a disease similar to SLE. 5-aminolevulinic acid (5-ALA) is a key progenitor of heme, and its combination with sodium ferrous citrate (SFC) can up-regulate the heme oxygenase (HO-1) expression, resulting in an anti-inflammatory effect. While HO-1 had been reported to be involved in T cell activation and can limit immune-based tissue damage through Treg suppression, which promotes effector response. Thus, we hypothesized that treatment with 5-ALA/SFC could ameliorate lupus nephritis in a mouse cGvHD model. Our results showed that 5-ALA/SFC-treatment significantly decreased the anti-double-stranded DNA (ds-DNA) autoantibodies, blood urea nitrogen (BUN) and creatinine (Cre) levels, reduced kidney inflammatory dendritic cells (DCs) and B cell activation, and increased the regulatory T cells (Tregs) at nine weeks. Furthermore, 5-ALA/SFC suppressed mRNA expression of TNF-α, IL-1ß, IFN-γ and markers on DCs. In addition, we also found that 5-ALA/SFC treatment increased the HO-1 expression on donor-derived DCs and Tregs concurrently, increased the number of Tregs, and reduced the population of activated DCs, B cells and CD8+ T cells at three weeks (early stage of the disease). We thus identified a novel role of 5-ALA/SFC for therapeutically improving the symptoms of lupus nephritis in a mouse cGvHD model and expanded the current understanding of how this immunoregulatory agent can be used to generate beneficial immune responses and treat autoimmune disease.

Effects of 5-aminolevulinic acid with iron supplementation on respiratory responses to graded cycling and interval walking training achievement in older women over 75 yrs.

BACKGROUND: Exercise training above a given intensity is necessary to prevent age-associated physical disability and diseases; however, the physical and psychological barriers posed by deteriorated physical fitness due to aging may hinder older people from performing daily exercise training. Because 5-aminolevulinic acid (ALA), a precursor of heme, reportedly improves mitochondrial function, we examined whether ALA, combined with sodium ferrous citrate (SFC) for enhancement, improved aerobic capacity and voluntary exercise training achievement in older women aged over 75 yrs. METHODS: The study was conducted using a placebo-controlled, double-blind crossover design. Fifteen women aged ~78 yrs. with no exercise habits underwent two trials for 7 days each where they performed interval walking training (IWT), repeating fast and slow speeds of walking for 3 min each, at >70% and at ~40% of peak aerobic capacity for walking, respectively, with ALA+SFC (100 and 115 mg/day, respectively) or placebo supplement intake (CNT), with a 12-day washout period. Before and after each trial, subjects underwent a graded cycling test while having their oxygen consumption rate (V·O2), carbon dioxide production rate (V·CO2), and plasma lactate concentration ([Lac-]p) measured. Furthermore, during the supplement intake period, exercise intensity for IWT was measured by accelerometry. RESULTS: In ALA+SFC, the increases in V·O2 and V·CO2 during the graded cycling test were attenuated (both, P < 0.01) with a 13% reduction in [Lac-]p (P = 0.012) while none of these attenuated responses occurred in CNT (all, P > 0.46). Furthermore, energy expenditure and time during fast walking for IWT were 25% (P = 0.032) and 21% (P = 0.022) higher in ALA+SFC than in CNT. CONCLUSION: Thus, ALA+SFC supplementation improved aerobic capacity and thus increased fast-walking training achievement in older women.

5-Aminolevulinic acid combined with sodium ferrous citrate (5-ALA/SFC) ameliorated liver injury in a murine acute graft-versus-host disease model by reducing inflammation responses through PGC1-α activation.

Acute graft-versus-host disease (aGvHD) remains lethal as a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HSCT). Inflammatory responses play an important role in aGvHD. 5-Aminolevulinic acid combined with sodium ferrous citrate (5-ALA/SFC) has been widely reported to have a major effect on the anti-inflammatory response; however, these effects in aGvHD models have never been reported. In this study, a murine aGvHD model was developed by transferring spleen cells from donor B6/N (H-2kb) mice into recipient B6D2F1 (H-2kb/d) mice. In addition to evaluating manifestations in aGvHD mice, we analyzed the serum ALT/AST levels, liver pathological changes, infiltrating cells and mRNA expression of inflammation-related cytokines and chemokines. 5-ALA/SFC treatment significantly ameliorated liver injury due to aGvHD and decreased the population of liver-infiltrating T cells, resulting in a reduced expression of pro-inflammatory cytokines and chemokines. Furthermore, the mRNA expression proliferator-activated receptor-γcoactivator (PGC-1α) was enhanced, which might explain why 5-ALA/SFC treatment downregulates inflammatory signaling pathways. Our results indicated that 5-ALA/SFC can ameliorate liver injury induced by aGvHD through the activation of PGC-1α and modulation of the liver mRNA expression of inflammatory-related cytokines and chemokines. This may be a novel strategy for treating this disease.

Heterozygous disruption of ALAS1 in mice causes an accelerated age-dependent reduction in free heme, but not total heme, in skeletal muscle and liver.

5-Aminolevulinic acid (ALA) is the rate-limiting intermediate in heme biosynthesis in vertebrate species; a reaction catalyzed by the mitochondrial ALA synthase 1 (ALAS1) enzyme. Previously we reported that knockdown of the ubiquitously expressed ALAS1 gene in mice disrupts normal glucose metabolism, attenuates mitochondrial function and results in a prediabetic like phenotype when animals pass 20-weeks of age (Saitoh et al., 2018). Contrary to our expectations, the cytosolic and mitochondrial heme content of ALAS1 heterozygous (A1+/-) mice were similar to WT animals. Therefore, we speculated that regulatory "free heme" may be reduced in an age dependent manner in A1+/- mice, but not total heme. Here, we examine free and total heme from the skeletal muscle and liver of WT and A1+/- mice using a modified acetone extraction method and examine the effects of aging on free heme by comparing the amounts at 8-12 weeks and 30-36 weeks of age, in addition to the mRNA abundance of ALAS1. We found an age-dependent reduction in free heme in the skeletal muscle and liver of A1+/- mice, while WT mice showed only a slight decrease in the liver. Total heme levels showed no significant difference between young and aged WT and A1+/- mice. ALAS1 mRNA levels showed an age-dependent reduction similar to that of free heme levels, indicating that ALAS1 mRNA expression levels are a major determinant for free heme levels. The free heme pools in skeletal muscle tissue were almost 2-fold larger than that of liver tissue, suggesting that the heme pool varies across different tissue types. The expression of heme oxygenase 1 (HO-1) mRNA, which is expressed proportionally to the amount of free heme, were similar to those of free heme levels. Taken together, this study demonstrates that the free heme pool differs across tissues, and that an age-dependent reduction in free heme levels is accelerated in mice heterozygous for ALAS1, which could account for the prediabetic phenotype and mitochondrial abnormality observed in these animals.

Efficacy of 5-aminolevulinic acid and LED photodynamic therapy in cervical intraepithelial neoplasia: A clinical trial.

BACKGROUND: 5-Aminolaevulinic acid (5ALA) is a precursor of the strong sensitizer protoporphyrin IX (PpIX) in the heme synthesis pathway. We conducted aclinical trial designed to evaluate the efficacy and safety of 5ALA photodynamic therapy (PDT) using a light-emitting diode (LED) in patients with cervical intraepithelial neoplasia (CIN). METHODS: Data for 51 CIN patients who underwent 5ALA-PDT between 2012 and 2017 were prospectively analysed. After a 20 % 5ALA jelly formulation was topically applied to the cervix, the region was irradiated with red light at approximately 633 nm to excite PpIX for treatment. We estimated outcomes by cytology, pathology, and human papilloma virus (HPV) testing after PDT. RESULTS: Patients underwent two PDT sessions at one-week intervals during outpatient treatment and achieved favourable results without photosensitivity and severe adverse events. Over a long follow-up period, 96.1 % of all patients showed some positive effects, including approximately 70 % with a complete response (CR), 10 % with a partial response, and 15 % with downgrades. The HPV clearance rate in patients with CR was 79.4 %. Recurrence occurred in five patients who mostly remained HPV-positive after PDT. CONCLUSIONS: Based on our study, topical 5ALA-PDT using an LED light source potentially represents a safe treatment for CIN on an outpatient basis.

Heparanase is Involved in Leukocyte Migration.

Leukocyte migration is essential for exerting self-defense mechanisms. During the extravasation process, leukocytes transmigrate through the endothelial lining and the subendothelial basement membrane. Accumulating evidence supports the involvement of heparanase in this process. Altered cellular distribution resulting in relocalization of heparanase to the leading edge of migration is a key event to rapidly turn on the function of the enzyme during migration. This review presents current research investigating the cellular machinery that builds up a functional subcellular structure for leukocyte attachment to and degradation of the extracellular matrix. Recent advances in the understanding of the roles of heparanase in inflammatory diseases and pharmacological approaches to control heparanase-mediated actions during inflammation are also discussed.

Safety and Mode of Action of Diabetes Medications in comparison with 5-Aminolevulinic Acid (5-ALA).

5-Aminolevulinic acid (5-ALA) is a delta amino acid naturally present in every living cell of the human body. 5-ALA is produced in the mitochondria as the first product of the porphyrin synthesis pathway and composes heme; exogenously supplemented 5-ALA helps in upregulating mitochondrial functions. Mitochondrial dysfunction has been associated with the pathophysiology of diabetes mellitus. Thus, in this review, we evaluate the mechanisms of action and adverse effects of common medications used to treat type 2 diabetes mellitus as well as 5-ALA including its mechanism and possible use in diabetes management.

Chondroitin sulfate E blocks enzymatic action of heparanase and heparanase-induced cellular responses.

We examined whether chondroitin sulfates (CSs) exert inhibitory effects on heparanase (Hpse), the sole endoglycosidase that cleaves heparan sulfate (HS) and heparin, which also stimulates chemokine production. Hpse-mediated degradation of HS was suppressed in the presence of glycosaminoglycans derived from a squid cartilage and mouse bone marrow-derived mast cells, including the E unit of CS. Pretreatment of the chondroitin sulfate E (CS-E) with chondroitinase ABC abolished the inhibitory effect. Recombinant proteins that mimic pro-form and mature-form Hpse bound to the immobilized CS-E. Cellular responses as a result of Hpse-mediated binding, namely, uptake of Hpse by mast cells and Hpse-induced release of chemokine CCL2 from colon carcinoma cells, were also blocked by the CS-E. CS-E may regulate endogenous Hpse-mediated cellular functions by inhibiting enzymatic activity and binding to the cell surface.

5-ALA/SFC enhances HO-1 expression through the MAPK/Nrf2 antioxidant pathway and attenuates murine tubular epithelial cell apoptosis.

Cyclosporin A (CsA) is a common immunosuppressant, but its use is limited as it can cause chronic kidney injury. Oxidative stress and apoptosis play a key role in CsA-induced nephrotoxicity. This study investigated the protective effect of 5-aminolevulinic acid and iron (5-ALA/SFC) on CsA-induced injury in murine proximal tubular epithelial cells (mProx24). 5-ALA/SFC significantly inhibited apoptosis in CsA-treated mProx24 cells with increases in heme oxygenase (HO)-1, nuclear factor E2-related factor 2 (Nrf2), and p38, and Erk-1/2 phosphorylation. Moreover, 5-ALA/SFC suppressed production of reactive oxygen species in CsA-exposed cells and inhibition of HO-1 suppressed the protective effects of 5-ALA/SFC. In summary, 5-ALA/SFC may have potential for development into a treatment for the anti-nephrotoxic/apoptotic effects of CsA.

Photoirradiation after aminolevulinic acid treatment suppresses cancer cell proliferation through the HO-1/p21 pathway.

BACKGROUND: Photodynamic therapy (PDT) and diagnosis (PDD) using 5-aminolevulinic acid (ALA) to control the production of an intracellular photosensitizer, protoporphyrin IX (PpIX), are in common clinical use. Although various studies have been published regarding cell death analysis after photoirradiation by ALA-PDT, the changes in gene expressions induced by it are yet unclear. Here, we focused on studying gene expression and cell proliferation changes in cancer cells that survive photoirradiation. METHODS: HEK293 human embryonic kidney cells, MKN45 human gastric cells, and PC-3 human prostate cancer cells were selected for this research. Cell viability was measured using trypan blue and MTT assays. ALA-PDT experiments were performed using a calibrated LED irradiation module. Furthermore, mRNA and protein gene expression analysis were performed using our previously reported methods. RESULTS: mRNAs of PAI-1, HO-1, and p21 were upregulated after photoirradiation of HEK293, which was suppressed by N-acetyl-L-cysteine, a reactive oxygen species (ROS) scavenger. Primer array results in PC-3 cells and p21 and Ki-67 expression results in both PC-3 and MKN45 cells suggested that photoirradiation suppressed cell proliferation. Cell numbers post-photoirradiation revealed that the proliferation of surviving cells was suppressed in PC-3 and MKN45 cells. CONCLUSION: ALA-PDD or ALA-PDT can result in rapid ROS-induced cell death and may decrease long-term recurrence rates through several pathways including the HO-1/p21 pathway.