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

5-aminolaevulinic acid with sodium ferrous citrate alleviated kidney injury and fibrosis in a unilateral ureteral obstruction model

PURPOSE

This study aimed to investigate the potential therapeutic effects of 5-aminolaevulinic acid (5-ALA) combined with sodium ferrous citrate (SFC) on kidney injury and fibrosis in a mouse model of unilateral ureteral obstruction (UUO)-induced chronic kidney disease (CKD).

METHODS

A murine UUO model was used to mimic human CKD. The mice received daily intragastric administration of 5-ALA/SFC for 7 and 14 consecutive days. Serum creatinine (Cr) and blood urea nitrogen (BUN) levels and histological evaluations were performed to assess the renal function parameters underlying 5-ALA/SFC treatment in the UUO model. Differentially expressed genes (DEGs) were analyzed by RNA sequencing (RNA-Seq), and the results were validated by quantitative real-time PCR (qRT-PCR). The severity of renal fibrosis was evaluated using Sirius red and Masson's trichrome (MT) staining techniques, while the expression of fibrosis-related genes was examined using western blotting and immunohistochemistry.

RESULTS

Our findings demonstrated that 5-ALA/SFC treatment improved UUO-induced renal dysfunction, attenuated tubular damage, and significantly reduced serum Cr and BUN levels as well as the mRNA expression and secretion of pro-inflammatory and programmed cell death-related cytokines in kidney tissues. Furthermore, 5-ALA/SFC suppressed renal tissue fibrosis and downregulated the mRNA and protein expression of fibrosis-related genes. Notably, treatment with 5-ALA/SFC led to the significant upregulation of protein expression levels of PPAR gamma-coactivator-1α (PGC-1α), indicating its role in inhibiting inflammation and fibrosis through the activation of the PGC-1α signaling pathway.

CONCLUSION

5-ALA/SFC exhibits renoprotective effects in UUO-induced CKD by attenuating inflammation, cell death, and suppressing renal fibrosis. These findings suggest a specific renal protective mechanism for 5-ALA/SFC, highlighting its potential as a novel therapeutic agent for human CKD treatment.

Therapeutic potential of 5-aminolevulinic acid in metabolic disorders: Current insights and future directions

5-Aminolevulinic acid (5-ALA) is an essential compound in the biosynthesis of heme, playing a critical role in various physiological processes within the human body. This review provides the thorough analysis of the latest research on the molecular mechanisms and potential therapeutic benefits of 5-ALA in managing metabolic disorders. The ability of 5-ALA to influence immune response and inflammation, oxidative/nitrosative stress, antioxidant system, mitochondrial functions, as well as carbohydrate and lipid metabolism, is mediated by molecular mechanisms associated with the suppression of the transcription factor NF-κB signaling pathway, activation of the transcription factor Nrf2/heme oxygenase-1 (HO-1) system leading to the formation of heme-derived reaction products (carbon monoxide, ferrous iron, biliverdin, and bilirubin), which may contribute to HO-1-dependent cytoprotection through antioxidant and immunomodulatory effects. Additionally, it regulates the expression of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, cytochrome c oxidase subunit IV, uncoupling proteins UCP1 and UCP2, glucose transporters GLUT1 and GLUT2, and sterol regulatory element-binding protein 1c in relevant tissues. Randomized controlled trials have confirmed the effects of 5-ALA on glucose control in both prediabetic and diabetic patients, noting its safety and tolerability, as well as the safety of its combined use with oral hypoglycemic agents. Only minor side effects have been reported. However, the impact of 5-ALA on markers of systemic inflammation, oxidative and nitrosative stress, and dyslipidemia was not evaluated in these studies. At the same time, preparations of 5-ALA may potentially be effective not only in the treatment of prediabetes and type 2 diabetes mellitus (T2DM), but also in other conditions associated with systemic inflammation, oxidative or nitrosative stress, mitochondrial dysfunction, as well as disorders of carbohydrate and lipid metabolism. It has been concluded that the promising advancement of formulations containing 5-ALA may pave the way for new strategies in preventing and treating these diseases, with subsequent preclinical and clinical trials likely to follow.

Exploring the therapeutic potential of "Tianyu" medicine pair in rheumatoid arthritis: an integrated study combining LC-MS/MS, bioinformatics, network pharmacology, and experimental validation

Background

Rheumatoid arthritis (RA) is a widespread chronic autoimmune disease that primarily causes joint inflammation and damage. In advanced stages, RA can result in joint deformities and loss of function, severely impacting patients' quality of life. The "Tianyu" pair (TYP) is a traditional Chinese medicine formulation developed from clinical experience and has shown some effectiveness in treating RA. However, its role in the complex biological mechanisms underlying RA remains unclear and warrants further investigation.

Methods

We obtained gene sequencing data of synovial tissues from both RA patients and healthy individuals using two gene microarrays, GSE77298 and GSE55235, from the GEO database. Through an integrated approach involving bioinformatics, machine learning, and network pharmacology, we identified the core molecular targets of the "Tianyu" medicine pair (TYP) for RA treatment. Liquid chromatography-mass spectrometry was then employed to analyze the chemical components of TYP. To validate our findings, we conducted animal experiments with Wistar rats, comparing histopathological and key gene expression changes before and after TYP treatment.

Results

Our data analysis suggests that the onset of RA may be associated with inflammation-related immune cells involved in both adaptive and innate immune responses. Potential key targets for TYP treatment in RA include AKR1B10, MMP13, FABP4, NCF1, SPP1, COL1A1, and RASGRP1. Among the components of TYP, Kaempferol, Quercetin, and Salidroside were identified as key, with MMP13 and NCF1 showing the strongest binding affinity to these compounds. Animal experiments confirmed the findings from bioinformatics and network pharmacology, validating the key targets and therapeutic effects of TYP in treating RA.

Conclusion

Our study reveals that TYP has potential clinical value in the treatment of rheumatoid arthritis. This research enhances our understanding of RA's pathogenesis and provides insight into potential therapeutic mechanisms.

The Impact of 5-Aminolevulinic Acid Supplementation on Redox Balance and Aerobic Capacity

We examined the impact of 5-aminolevulinic acid (5-ALA) and sodium-ferrous-citrate supplementation on aerobic capacity and redox balance through a placebo-controlled, double-blind trial. Fourteen healthy volunteers were randomly assigned to Pla + ALA (4-week placebo followed by 4-week 5-ALA supplementation) or ALA + Pla (4-week 5-ALA supplement followed by a 4-week placebo) group and administered 5-ALA (25 mg/day) or placebo once daily. The participants underwent submaximal incremental cycling tests at weeks 0, 2, 4, 6, and 8. In the cycling test at week 0, individual load-intensity stages required for blood lactate levels >2 mmol/L (lactate threshold, LT) and 4 mmol/L (onset of blood lactate accumulation, OBLA) were determined. The heart rate (HR), blood lactate (La), and oxidative stress markers (diacron reactive oxygen metabolite, d-ROMs; biological antioxidant potential, BAP) were measured at resting, LT, and OBLA states in each cycling test. Marker values were not significantly different between the groups. HR, La, and d-ROMs at resting, LT, and OBLA states were not significantly different among the conditions. BAP and BAP/d-ROMs ratios were significantly different in the OBLA state at week 4 of the 5-ALA group compared with that of the placebo group (p < 0.05). In conclusion, 5-ALA supplementation might improve redox balance during high-intensity aerobic exercise.

Nrf2/HO-1 as a therapeutic target in renal fibrosis

Chronic kidney disease (CKD) is one of the most prevalent chronic diseases and affects between 10 and 14 % of the world's population. The World Health Organization estimates that by 2040, the disease will be fifth in prevalence. End-stage CKD is characterized by renal fibrosis, which can eventually lead to kidney failure and death. Renal fibrosis develops due to multiple injuries and involves oxidative stress and inflammation. In the human body, nuclear factor erythroid 2-related factor 2 (Nrf2) plays an important role in the expression of antioxidant, anti-inflammatory, and cytoprotective genes, which prevents oxidative stress and inflammation damage. Heme oxygenase (HO-1) is an inducible homolog influenced by heme products and after exposure to cellular stress inducers such as oxidants, inflammatory chemokines/cytokines, and tissue damage as an outcome or downstream of Nrf2 activation. HO-1 is known for its antioxidative properties, which play an important role in regulating oxidative stress. In renal diseases-induced tissue fibrosis and xenobiotics-induced renal fibrosis, Nrf2/HO-1 has been targeted with promising results. This review summarizes these studies and highlights the interesting bioactive compounds that may assist in attenuating renal fibrosis mediated by HO-1 activation. In conclusion, Nrf2/HO-1 signal activation could have a renoprotective effect strategy against CKD caused by oxidative stress, inflammation, and consequent renal fibrosis.

5-Aminolevulinic acid/sodium ferrous citrate improves the quality of heat-stressed bovine oocytes by reducing oxidative stress

A high temperature-humidity index during summer has deleterious effects on mitochondrial function, reducing oocyte developmental competence. 5-Aminolevulinic acid (5-ALA) and sodium ferrous citrate (SFC) are both known to support mitochondrial function and have strong anti-oxidant and anti-apoptotic activities. This study aimed to determine the mechanism of action of 5-ALA/SFC on oocyte quality. Bovine oocytes were collected from medium-sized follicles during summer (July-September, temperature-humidity index:76.6), cultured with 0, 1, 2, 4, and 8 µM 5-ALA with SFC at a molar ratio of 1:0.125, fertilized, and cultured for 10 days. The addition of 8/1 µM 5-ALA/SFC had a deleterious effect on oocyte cleavage rate in comparison with control oocytes, but did not affect the blastocyst rate, while 1/0.125 µM 5-ALA/SFC had a significantly higher increase in blastocyst rate than 8/1 µM 5-ALA/SFC. The addition of 1/0.125 and 2/0.25 µM 5-ALA/SFC improved oocyte quality by increasing the mitochondrial distribution pattern and metaphase-II oocytes, reducing reactive oxygen species and upregulating nuclear factor erythroid-2-related factor 2, heme oxygenase-1, and superoxide dismutase-1 in oocytes, and nuclear factor erythroid-2-related factor 2 and mitochondrial transcription factor A in cumulus cells. These results indicate that 1/0.125 and 2/0.25 µM 5-ALA/SFC may support oocyte quality and developmental competence and provide anti-oxidant actions in cumulus-oocyte complexes.

Sodium Ferrous Citrate and 5-Aminolevulinic Acid Exert a Therapeutic Effect on Endotoxin-Induced Uveitis in Rats

The metabolism of 5-aminolevulinic acid (ALA) is more efficient when combined with sodium ferrous citrate (SFC). Our previous study revealed that oral administration of ALA, which has anti-inflammatory properties, and SFC (ALA/SFC) immediately before lipopolysaccharide (LPS) inoculation suppressed endotoxin-induced uveitis (EIU) in rats. However, the therapeutic effect of ALA/SFC post-administration remains unexplored. Hence, this study aimed to evaluate the therapeutic efficacy of ALA/SFC on EIU in rats, which were administered with a gastric gavage of ALA/SFC (100/157 mg/kg) or prednisolone (Pred, 10 mg/kg) after 4 h of LPS inoculation. The treatment groups showed ameliorated clinical scores, inflammatory cells, protein levels in the aqueous humor (AqH), and histopathologic evaluation 24 h after LPS inoculation. Furthermore, the treatment groups had reduced tumor necrosis factor-α, nitric oxide, prostaglandin E2, and interleukin-6 levels in the AqH. ALA/SFC demonstrated an anti-inflammatory effect equivalent to that demonstrated by Pred. These findings indicate that ALA/SFC exerts a therapeutic effect on EIU in rats, indicating its clinical usefulness in uveitis treatment.

5-Aminolevrinic Acid Exhibits Dual Effects on Stemness in Human Sarcoma Cell Lines under Dark Conditions

5-aminolevulinic acid (ALA) is used for tumor-targeting phototherapy because it is converted to protoporphyrin IX (PPIX) upon excitation and induces phototoxicity. However, the effect of ALA on malignant cells under unexcited conditions is unclear. This information is essential when administering ALA systemically. We used sarcoma cell lines that usually arise deep in the body and are rarely exposed to light to examine the effects of ALA treatment under light (daylight lamp irradiation) and dark (dark room) conditions. ALA-treated human SW872 liposarcoma cells and human MG63 osteosarcoma cells cultured under light exhibited growth suppression and increased oxidative stress, while cells cultured in the dark showed no change. However, sphere-forming ability increased in the dark, and the expression of stem-cell-related genes was induced in dark, but not light, conditions. ALA administration increased heme oxygenase 1 (HO-1) expression in both cell types; when carbon monoxide (CO), a metabolite of HO-1, was administered to sarcoma cells via carbon-monoxide-releasing molecule 2 (CORM2), it enhanced sphere-forming ability. We also compared the concentration of biliverdin (BVD) (a co-product of HO-1 activity alongside CO) with sphere-forming ability when HO-1 activity was inhibited using ZnPPIX in the dark. Both cell types showed a peak in sphere-forming ability at 60–80 μM BVD. Furthermore, a cell death inhibitor assay revealed that the HO-1-induced suppression of sphere formation was rescued by apoptosis or ferroptosis inhibitors. These findings suggest that in the absence of excitation, ALA promotes HO-1 expression and enhances the stemness of sarcoma cells, although excessive HO-1 upregulation induces apoptosis and ferroptosis. Our data indicate that systemic ALA administration induces both enhanced stemness and cell death in malignant cells located in dark environments deep in the body and highlight the need to pay attention to drug delivery and ALA concentrations during phototherapy.

5-ALA Attenuates the Palmitic Acid-Induced ER Stress and Apoptosis in Bovine Mammary Epithelial Cells

The conservation of mammary gland physiology by maintaining the maximum number of mammary epithelial cells (MECs) is of the utmost importance for the optimum amount of milk production. In a state of negative energy balance, palmitic acid (PA) reduces the number of bovine MECs. However, there is no effective strategy against PA-induced apoptosis of MECs. In the present study, 5-aminolevulinic acid (5-ALA) was established as a remedial agent against PA-induced apoptosis of MAC-T cells (an established line of bovine MECs). In PA-treated cells, the apoptosis-related genes BCL2 and BAX were down- and upregulated, respectively. The elevated expression of major genes of the unfolded protein response (UPR), such as CHOP, a proapoptotic marker (C/EBP homologous protein), reduced the viability of PA-treated MAC-T cells. In contrast, 5-ALA pretreatment increased and decreased BCL2 and BAX expression, respectively. Moreover, cleaved caspase-3 protein expression was significantly reduced in the 5-ALA-pretreated group in comparison with the PA group. The downregulation of major UPR-related genes, including CHOP, extended the viability of MAC-T cells pretreated with 5-ALA and also reduced the enhanced intensity of the PA-induced expression of phospho-protein kinase R-like ER kinase. Moreover, the enhanced expression of HO-1 (antioxidant gene heme oxygenase) by 5-ALA reduced PA-induced oxidative stress (OxS). HO-1 is not only protective against OxS but also effective against ER stress. Collectively, these findings offer new insights into the protective effects of 5-ALA against PA-induced apoptosis of bovine MECs.

Single-arm, open-label pilot intervention study to investigate an effect of oral 5-aminolevulinic acid plus sodium ferrous citrate on glucocorticoid reduction in patients with adult-onset Still disease: Study protocol for clinical trial (SPIRIT compliant)

BACKGROUND

Glucocorticoids are an important class of medication for patients with adult-onset Still disease (AOSD), however, relapse following glucocorticoid reduction and adverse events due to long-term effects of glucocorticoid are still problematic. It is of course essential to minimize the risk of treatment. Immunosuppressive therapies such as methotrexate and biologics including tocilizumab are used in glucocorticoid-dependent patients with AOSD, but no second-line treatments for patients with glucocorticoid dependence have been established yet. Given that these drugs also have the potential to cause adverse events, alternative treatments are sought. Recently, elevated heme oxygenase-1 (HO-1) has been reported in the serum of patients with AOSD, suggesting that HO-1 activity contributes to AOSD pathogenesis and may represent a new therapeutic target for the treatment of AOSD. The amino acid 5-aminolevulinic acid (5-ALA) is a non-proteinogenic δ amino acid in human body. An addition of ferrous iron to 5-ALA enhances heme biosynthesis. The increase in heme in vivo induces HO-1 production, a heme-degrading enzyme. Elevated HO-1 has been suggested to contribute to the pathogenesis of AOSD, and administration of 5-ALA and ferrous iron may be a potential treatment for AOSD.

METHODS/DESIGN

This study is a single-arm, open-label pilot intervention study using clinical endpoints to investigate the effects of oral 5-ALA with sodium ferrous citrate on glucocorticoid reduction in patients with AOSD receiving glucocorticoid therapy.

DISCUSSION

This pilot intervention study will provide evidence regarding the effectiveness and safety of 5-ALA/sodium ferrous citrate as a potential new therapeutic agent for glucocorticoid-dependent patients with AOSD.

TRIAL REGISTRATION

This study was registered in the Japan Registry of Clinical Trials (https://jrct.niph.go.jp) on January 14, 2020 as jRCTs071190042.

Protective effects of 5-aminolevulinic acid on heat stress in bovine mammary epithelial cells

OBJECTIVE

Cells have increased susceptibility to activation of apoptosis when suffering heat stress (HS). An effective supplementation strategy to mimic heat-induced apoptosis of bovine mammary epithelial cells (MECs) is necessary to maintain optimal milk production. This study aimed to investigate possible protective effects of the anti-apoptotic activity of 5-aminolevulinic acid (5-ALA) against HS-induced damage of bovine MECs.

METHODS

Bovine MECs were pretreated with or without 5-ALA at concentrations of 10, 100, and 500 μM for 24 h followed by HS (42.5°C for 24 h and 48 h). Cell viability was measured with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays. Real-time quantitative polymerase chain reaction and Western blotting were used to explore the regulation of genes associated with apoptosis, oxidative stress, and endoplasmic reticulum (ER) stress genes.

RESULTS

We found that 5-ALA induces cytoprotection via inhibition of apoptosis markers after HS-induced damage. Pretreatment of bovine MECs with 5-ALA resulted in dramatic upregulation of mRNA for nuclear factor erythroid-derived 2-like factor 2, heme oxygenase-1, and NAD(P)H quinone oxidoreductase 1, all of which are antioxidant stress genes. Moreover, 5-ALA pretreatment significantly suppressed HS-induced ER stress-associated markers, glucose-regulated protein 78, and C/EBP homologous protein expression levels.

CONCLUSION

5-ALA can ameliorate the ER stress in heat stressed bovine MEC via enhancing the expression of antioxidant gene.

Heme-Oxygenase and Kidney Transplantation: A Potential for Target Therapy?

Kidney transplantation is a well-established therapy for patients with end-stage renal disease. While a significant improvement of short-term results has been achieved in the short-term, similar results were not reported in the long-term. Heme-oxygenase (HO) is the rate-limiting enzyme in heme catabolism, converting heme to iron, carbon monoxide, and biliverdin. Heme-oxygenase overexpression may be observed in all phases of transplant processes, including brain death, recipient management, and acute and chronic rejection. HO induction has been proved to provide a significant reduction of inflammatory response and a reduction of ischemia and reperfusion injury in organ transplantation, as well as providing a reduction of incidence of acute rejection. In this review, we will summarize data on HO and kidney transplantation, suggesting possible clinical applications in the near future to improve the long-term outcomes.

MicroRNA-mediated regulation of Nrf2 signaling pathway: Implications in disease therapy and protection against oxidative stress

MicroRNAs (miRs) are small non-coding pieces of RNA that are involved in a variety of physiologic processes such as apoptosis, cell proliferation, cell differentiation, cell cycle and cell survival. These multifunctional nucleotides are also capable of preventing oxidative damages by modulating antioxidant defense systems in a variety of milieu, such as in diabetes. Although the exact molecular mechanisms by which miRs modulate the antioxidant defense elements are unclear, some evidence suggests that they may exert these effects via nuclear factor erythroid 2-related factor 2 (Nrf2) signaling pathway. This intracellular mechanism is crucial in the maintenance of the physiologic redox balance by regulating the expression and activity of various cellular antioxidative defense elements and thereby plays a pivotal role in the development of oxidative stress. Any impairment in the Nrf2 signaling pathway may result in oxidative damage-dependent complications such as various diabetic complications, neurological disorders and cancer. In the current review, we discuss the modulatory effects of miRs on the Nrf2 signaling pathway, which can potentially be novel therapeutic targets.