Anti-cancer actions of carnosine and the restoration of normal cellular homeostasis

The one-humped camel: The animal of future, potential alternative red meat, technological suitability and future perspectives

The 2020 world population data sheet indicates that world population is projected to increase from 7.8 billion in 2020 to 9.9 billion by 2050 (Increase of more than 25%). Due to the expected growth in human population, the demand for meats that could improve health status and provide therapeutic benefits is also projected to rise. The dromedary also known as the Arabian camel, or one-humped camel ( Camelus dromedarius), a pseudo ruminant adapted to arid climates, has physiological, biological and metabolic characteristics which give it a legendary reputation for surviving in the extreme conditions of desert environments considered restrictive for other ruminants. Camel meat is an ethnic food consumed across the arid regions of Middle East, North-East Africa, Australia and China. For these medicinal and nutritional benefits, camel meat can be a great option for sustainable meat worldwide supply. A considerable amount of literature has been published on technological aspects and quality properties of beef, lamb and pork but the information available on the technological aspects of the meat of the one humped camel is very limited. Camels are usually raised in less developed countries and their meat is as nutritionally good as any other traditional meat source. Its quality also depends on the breed, sex, age, breeding conditions and type of muscle consumed. A compilation of existing literature related to new technological advances in packaging, shelf-life and quality of camel meat has not been reviewed to the best of our knowledge. Therefore, this review attempts to explore the nutritional composition, health benefits of camel meat, as well as various technological and processing interventions to improve its quality and consumer acceptance. This review will be helpful for camel sector and highlight the potential for global marketability of camel meat and to generate value added products.

To elucidate the mechanism of "Scrophulariae Radix-Fritillaria" in goiter by integrated metabolomics and serum pharmaco-chemistry

The pharmacodynamic substances in "Scrophulariae Radix-Fritillaria" and the molecular mechanisms underlying its therapeutic effects against goiter were analyzed through metabolomics and serum pharmaco-chemistry. A rat model of goiter was established using propylthiouracil (PTU), and the animals were treated using "Scrophulariae Radix-Fritillaria." The efficacy of the drug pair was evaluated in terms of thyroid gland histopathology and blood biochemical indices. Serum and urine samples of the rats were analyzed by UPLC-Q-TOF/MS. Principal component analysis (PCA) and orthogonal partial least squares discriminant analysis (OPLS-DA) were performed to screen potential biomarkers in urine and the corresponding metabolic pathways. The blood components of "Scrophulariae Radix-Fritillaria" were also identified, and their correlation with urine biomarkers was analyzed in order to screen for potential bioactive compounds. "Scrophulariae Radix-Fritillaria" mitigated injury to thyroid tissues and normalized the levels of the thyroid hormones FT3, FT4, and TSH. We also identified 22 urine biomarkers related to goiter, of which 19 were regulated by "Scrophulariae Radix-Fritillaria." Moreover, urine biomarkers are involved in tryptophan metabolism, steroid hormone biosynthesis, and beta-alanine metabolism, and these pathways may be targeted by the drug pair. In addition, 47 compounds of "Scrophulariae Radix-Fritillaria" were detected by serum pharmacochemistry, of which nine components, namely, syringic acid, paeonol, cedrol, and cis-ferulic acid, fetisinine, aucubigenin, linolenic acid, ussuriedine, and 5-(methylsulfanyl)pentanenitrile, were identified as potential effective substances against goiter. To summarize, we characterized the chemical components and mechanisms of "Scrophulariae Radix-Fritillaria" involved in the treatment of goiter, and our findings provide an experimental basis for its clinical application.

In silico Evaluation of Ferulic Acid Based Multifunctional Conjugates as Potential Drug Candidates

BACKGROUND

Recent research has shown that ferulic acid (FA, trans-4-hydroxy-3- methoxycinnamic acid) has remarkable antioxidant properties and a wide range of biological activities. Conjugation of two or more biologically active compounds to produce a novel molecular scaffold is justified by the need to enhance biological activity against a single target or obtain a conjugate that behaves as a multi-target-directed ligand. In addition, the conjugation strategy decreases dose-dependent side effects by promoting the use of smaller doses of conjugated components to treat the disease. Moreover, the patient's compliance is positively affected when conjugating two active compounds into a single more active compound as this reduces the number of pills to be taken daily.

OBJECTIVE

This study aims to shed light on studies that design and synthesize FA-based hybrid compounds with enhanced biological activities and to in silico assess these compounds as potential drug candidates.

METHODS

The conjugate compounds were found by searching the literature using the keywords (ferulic acid-based hybrid or ferulic acid-based conjugate). To study conjugate pharmacokinetic parameters and toxicity (ADMET), software suites from Biovia Inc. (San Diego, California) were integrated into Discovery Studio 4.5. The structures were created using ChemDraw Ultra 7.0.

RESULTS

14 conjugates exhibiting variable biological activities were collected and three of them (compounds 3,5, and 6) in addition to the cis FA (compound 12) are the best-predicted compounds with low Daphnia toxicity and hepatotoxicity with acceptable pharmacokinetic properties.

CONCLUSION

Cis FA, FA conjugates 3,5, and 6 act as good drug candidates that can be used to modify new hits.

Anticancer actions of carnosine in cellular models of prostate cancer

Treatments for organ-confined prostate cancer include external beam radiation therapy, radical prostatectomy, radiotherapy/brachytherapy, cryoablation and high-intensity focused ultrasound. None of these are cancer-specific and are commonly accompanied by side effects, including urinary incontinence and erectile dysfunction. Moreover, subsequent surgical treatments following biochemical recurrence after these interventions are either limited or affected by the scarring present in the surrounding tissue. Carnosine (β-alanyl-L-histidine) is a histidine-containing naturally occurring dipeptide which has been shown to have an anti-tumorigenic role without any detrimental effect on healthy cells; however, its effect on prostate cancer cells has never been investigated. In this study, we investigated the effect of carnosine on cell proliferation and metabolism in both a primary cultured androgen-resistant human prostate cancer cell line, PC346Flu1 and murine TRAMP-C1 cells. Our results show that carnosine has a significant dose-dependent inhibitory effect in vitro on the proliferation of both human (PC346Flu1) and murine (TRAMP-C1) prostate cancer cells, which was confirmed in 3D-models of the same cells. Carnosine was also shown to decrease adenosine triphosphate content and reactive species which might have been caused in part by the increase in SIRT3 also shown after carnosine treatment. These encouraging results support the need for further human in vivo work to determine the potential use of carnosine, either alone or, most likely, as an adjunct therapy to surgical or other conventional treatments.

Inhibitory Potential of Carnosine and Aminoguanidine Towards Glycation and Fibrillation of Albumin: In-vitro and Simulation Studies

Carnosine is beta-alanyl histidine, a dipeptide, endogenously produced in our body by the carnosine synthase enzyme. It is an antioxidant, thus protecting from the deleterious effect of advanced glycation end products (AGEs). Similarly, aminoguanidine (AG) also prevents AGEs formation by scavenging free radicals such as reactive oxygen species (ROS)/reactive carbonyl species (RCS). This study used experimental and computational techniques to perform a comparative analysis of carnosine and AG and their inhibiting properties against glycated human serum albumin (HSA). Fructose-mediated glycation of albumin produced fluorescent structures, such as pentosidine and malondialdehyde. These AGEs were significantly reduced by carnosine and AG. At 20 mM, carnosine and AG quenches pentosidine fluorescence by 66% and 83%, respectively. A similar inhibitory effect was observed for malondialdehyde. Protein hydrophobicity and tryptophan fluorescence were restored in the presence of carnosine and AG. Aminoguanidine decreased fibrillation in HSA, while carnosine did not significantly affect aggregation/fibrillation. In addition, molecular docking study observed binding scores of -5.90 kcal/mol and -2.59 kcal/mol by HSA-aminoguanidine and HSA-carnosine complex, respectively. Aminoguanidine forms one conventional hydrogen bond with ARG A:10 and a salt bridge with ASP A:13, ASP A:259, ASP A:255, and ASP A:256 from the amine group. Similarly, carnosine forms only hydrogen bonds with GLU A:501 and GLN A:508 from the amine and hydroxy group. The root mean square deviation (RMSD) calculated from simulation studies was 1 nm upto 70 ns for the HSA-aminoguanidine complex and the spectrum of HSA-carnosine was significantly deviated and not stabilized. The superior inhibitory activity of aminoguanidine could be due to additional salt bridge bonding with albumin. Conclusively, aminoguanidine can be the better treatment choice for diabetes-associated neurological diseases.

Transcriptomics and metabolomics reveal improved performance of Hu sheep on hybridization with Southdown sheep

Consumers are increasingly demanding high-quality mutton. Cross breeding can improve meat quality and is widely used in sheep breeding. However, little is known about the molecular mechanism of cross breeding sheep meat quality. In this study, male Southdown and female Hu sheep were hybridized. The slaughter performance and longissimus dorsi quality of the 6-month-old hybrid offspring were measured, and the longissimus dorsi of the hybrid offspring was analyzed by transcriptomics and metabolomics to explore the effect of cross breeding on meat quality. The results showed that the production performance of Southdown × Hu F1 sheep was significantly improved, the carcass fat content was significantly decreased, and the eating quality of Southdown × Hu F1 sheep were better. Compared with the HS group (Hu × Hu), the NH group (Southdown × Hu) had 538 differentially expressed genes and 166 differentially expressed metabolites (P < 0.05), which were significantly enriched in amino acid metabolism and other related pathways. Up-regulated genes METTL21C, PPARGC1A and down-regulated gene WFIKKN2 are related to muscle growth and development. Among them, the METTL21C gene, which is related to muscle development, was highly correlated with carnosine, a metabolite related to meat quality (correlation > 0.6 and P < 0.05). Our results provide further understanding of the molecular mechanism of cross breeding for sheep muscle growth and meat quality optimization.

Carnosine alleviates cisplatin-induced acute kidney injury by targeting Caspase-1 regulated pyroptosis

Acute kidney injury (AKI) is a syndrome characterized by rapid loss of renal excretory function. Its underlying mechanisms remain unclear. Pyroptosis, a form of programmed cell death, plays an important role in AKI. It is characterized by cell swelling and membrane rupture, triggering the release of cellular contents and activating robust inflammatory responses. Carnosine, a dipeptide with antioxidant and anti-inflammatory properties, has therapeutic effects in AKI. However, the mechanism by which carnosine treats AKI-associated pyroptosis remains unexplored. In this study, we investigated the protective effect of carnosine on renal tubule cells using in vivo and in vitro models of AKI. We found that carnosine therapy significantly alleviated altered serum biochemical markers and histopathological changes in mice with cisplatin-induced AKI. It also reduced the levels of inflammation and pyroptosis. These results were consistent with those seen in human kidney tubular epithelial cells (HK-2) treated with cisplatin. Through molecular docking and cellular thermal shift assay, we identified caspase-1 as a target of carnosine. By knocking down caspase-1 in HK-2 cells using caspase-1 siRNA, we demonstrated that carnosine did not exhibit a protective role in cisplatin-induced HK-2 cells. This study provides the first evidence that carnosine alleviates damage to kidney tubular epithelial cells by targeting caspase-1 and inhibiting pyroptosis. Therefore, carnosine holds promise as a potential therapeutic agent for AKI, with caspase-1 representing an effective therapeutic target in this pathology.

Evaluation of anti-cancer effects of carnosine and melittin-loaded niosomes in MCF-7 and MDA-MB-231 breast cancer cells

Background: We investigated the anti-cancer effect of carnosine-loaded niosomes (Car-NIO) and melittin-loaded niosomes (Mel-NIO) with olaparib in breast cancer cell lines (MCF-7 and MDA-MB-231). Methods: The thin film method was used for preparing the niosomes and characterized in terms of morphology, size, and polydispersity index (PDI). We further evaluated the impact of these peptides on breast cancer cells viability, RT-qPCR assays, malondialdehyde (MDA) activity, and cell cycle progression, to determine if these are linked to carnosine and melittin's anti-proliferative properties. Results: Car-NIO and Mel-NIO in vitro study inhibited cancer cell viability. They have also upregulated the expression of protein 53 (P53), BCL2-Associated X Protein (Bax), caspase-9, caspase-3, programmed cell death 4 (PDCD4), and Forkhead box O3 (FOXO3), while downregulated the expression of B-cell lymphoma 2 (Bcl2), poly (ADP-ribose) polymerase (PARP 1), and MicroRNA-183 (miRNA-183). The MCF-7 cells were arrested at the G2/M phase in Car-NIO, on the other hand, the MDA-MB-231 cells were arrested at the S phase. While the Mel-NIO and olaparib arrested the MCF-7 and MDA-MB-231 cells at the G0/1 phase. Conclusion: Our study successfully declared that Mel-NIO had more anti-cancer effects than Car-NIO in both MCF-7 and MDA-MB-231 breast cancer cells.

The Impact of Pigment-Epithelium-Derived Factor on MCF-7 Cell Metabolism in the Context of Glycaemic Condition

Studies have demonstrated that pigment-epithelium-derived factor (PEDF) is a robust inhibitor of tumour growth and development, implying that this may serve as a promising target for therapeutic intervention. However, the precise impact of PEDF on cancerous cell metabolic pathways remains uncertain despite ongoing research. In this light, this study aimed to employ a metabolomics approach for understanding the metabolic reprogramming events in breast cancer across different glycaemic loads and their response to PEDF. Gas chromatography-quadrupole mass spectrometry (GC/Q-MS) analysis revealed metabolic alterations in ER+ human cell line MCF-7 cells treated with PEDF under varying glycaemic conditions. The identification of significantly altered metabolites was accomplished through MetaboAnalyst (v.5.0) and R packages, which enabled both multivariate and univariate analyses. Out of the 48 metabolites identified, 14 were chosen based on their significant alterations in MCF-7 cells under different glycaemic conditions and PEDF treatment (p < 0.05, VIP > 0.8). Dysregulation in pathways associated with amino acid metabolism, intermediates of the TCA cycle, nucleotide metabolism, and lipid metabolism were detected, and they exhibited different responses to PEDF. Our results suggest that PEDF has a diverse influence on the metabolism of MCF-7 cells in both normo- and hyperglycaemic environments, thereby warranting studies using patient samples to correlate our findings with clinical response in the future.

Carnosine and Beta-Alanine Supplementation in Human Medicine: Narrative Review and Critical Assessment

The dipeptide carnosine is a physiologically important molecule in the human body, commonly found in skeletal muscle and brain tissue. Beta-alanine is a limiting precursor of carnosine and is among the most used sports supplements for improving athletic performance. However, carnosine, its metabolite N-acetylcarnosine, and the synthetic derivative zinc-L-carnosine have recently been gaining popularity as supplements in human medicine. These molecules have a wide range of effects—principally with anti-inflammatory, antioxidant, antiglycation, anticarbonylation, calcium-regulatory, immunomodulatory and chelating properties. This review discusses results from recent studies focusing on the impact of this supplementation in several areas of human medicine. We queried PubMed, Web of Science, the National Library of Medicine and the Cochrane Library, employing a search strategy using database-specific keywords. Evidence showed that the supplementation had a beneficial impact in the prevention of sarcopenia, the preservation of cognitive abilities and the improvement of neurodegenerative disorders. Furthermore, the improvement of diabetes mellitus parameters and symptoms of oral mucositis was seen, as well as the regression of esophagitis and taste disorders after chemotherapy, the protection of the gastrointestinal mucosa and the support of Helicobacter pylori eradication treatment. However, in the areas of senile cataracts, cardiovascular disease, schizophrenia and autistic disorders, the results are inconclusive.

Post-Translational Modifications Evoked by Reactive Carbonyl Species in Ultraviolet-A-Exposed Skin: Implication in Fibroblast Senescence and Skin Photoaging

Photoaging is an accelerated form of aging resulting from skin exposure to ultraviolet (UV) radiation. UV-A radiation deeply penetrates the dermis and triggers the generation of reactive oxygen species (ROS) which promotes damage to DNA, lipids and proteins. Lipid peroxidation results from the oxidative attack of polyunsaturated fatty acids which generate a huge amount of lipid peroxidation products, among them reactive carbonyl species (RCS) such as α, β-unsaturated hydroxyalkenals (e.g., 4-hydroxynonenal), acrolein or malondialdehyde. These highly reactive agents form adducts on free NH2 groups and thiol residues on amino acids in proteins and can also modify DNA and phospholipids. The accumulation of RCS-adducts leads to carbonyl stress characterized by progressive cellular and tissular dysfunction, inflammation and toxicity. RCS-adducts are formed in the dermis of skin exposed to UV-A radiation. Several RCS targets have been identified in the dermis, such as collagen and elastin in the extracellular matrix, whose modification could contribute to actinic elastosis lesions. RCS-adducts may play a role in fibroblast senescence via the modification of histones, and the sirtuin SIRT1, leading to an accumulation of acetylated proteins. The cytoskeleton protein vimentin is modified by RCS, which could impair fibroblast motility. A better identification of protein modification and carbonyl stress in the dermis may help to develop new treatment approaches for preventing photoaging.

Preparation and Characterization of an Ancient Aminopeptidase Obtained from Ancestral Sequence Reconstruction for L-Carnosine Synthesis

As a biologically active peptide, L-carnosine has been widely used in the pharmaceutical, cosmetic and health care industries due to its various physiological properties. However, relatively little research is available regarding L-carnosine's enzymatic synthesis function. In this study, a potential enzyme sequence with the function of carnosine synthesizing was screened out using the ancestral sequence reconstruction (ASR) technique. Identified with L-carnosine synthesis activity, this enzyme was further confirmed using autoproteolytic phenomenon via Western blot and N-terminal sequencing. After purification, the enzymatic properties of LUCA-DmpA were characterized. The melting temperature (T_m) and denaturation enthalpy (ΔH) of LUCA-DmpA were 60.27 ± 1.24 °C and 1306.00 ± 26.73 kJ·mol^-1, respectively. Circular dichroism (CD) spectroscopy results showed that this ancestral enzyme was composed of α-helix (35.23 ± 0.06%), β-sheet (11.06 ± 0.06%), β-turn (23.67 ± 0.06%) and random coil (32.03 ± 0.06%). The enzyme was characterized with the optimal temperature and pH of 45 °C and 9.0, respectively. Notably, LUCA-DmpA was also characterized with remarkable pH tolerance based on the observation of more than 85% remaining enzymatic activity after incubation at different pH buffers (pH = 6-11) for 12 h. Additionally, rather than being improved or inhibited by metal ions, its enzymatic activity was found to be promoted by introducing organic solvent with a larger log P value. Based on these homology modeling results, the screened LUCA-DmpA is suggested to have further optimization potential, and thereafter to be offered as a promising candidate for real industrial applications.

Viability of Glioblastoma Cells and Fibroblasts in the Presence of Imidazole-Containing Compounds

The naturally occurring dipeptide carnosine (β-alanyl-L-histidine) specifically attenuates tumor growth. Here, we ask whether other small imidazole-containing compounds also affect the viability of tumor cells without affecting non-malignant cells and whether the formation of histamine is involved. Patient-derived fibroblasts and glioblastoma cells were treated with carnosine, L-alanyl-L-histidine (LA-LH), β-alanyl-L-alanine, L-histidine, histamine, imidazole, β-alanine, and L-alanine. Cell viability was assessed by cell-based assays and microscopy. The intracellular release of L-histidine and formation of histamine was investigated by high-performance liquid chromatography coupled to mass spectrometry. Carnosine and LA-LH inhibited tumor cell growth with minor effects on fibroblasts, and L-histidine, histamine, and imidazole affected viability in both cell types. Compounds without the imidazole moiety did not diminish viability. In the presence of LA-LH but not in the presence of carnosine, a significant rise in intracellular amounts of histidine was detected in all cells. The formation of histamine was not detectable in the presence of carnosine, LA-LH, or histidine. In conclusion, the imidazole moiety of carnosine contributes to its anti-neoplastic effect, which is also seen in the presence of histidine and LA-LH. Despite the fact that histamine has a strong effect on cell viability, the formation of histamine is not responsible for the effects on the cell viability of carnosine, LA-LH, and histidine.

Unveiling the Hidden Therapeutic Potential of Carnosine, a Molecule with a Multimodal Mechanism of Action: A Position Paper

Carnosine (β-alanyl-L-histidine) is a naturally occurring endogenous dipeptide and an over-the-counter food supplement with a well-demonstrated multimodal mechanism of action that includes the detoxification of reactive oxygen and nitrogen species, the down-regulation of the production of pro-inflammatory mediators, the inhibition of aberrant protein formation, and the modulation of cells in the peripheral (macrophages) and brain (microglia) immune systems. Since its discovery more than 100 years ago, a plethora of in vivo preclinical studies have been carried out; however, there is still substantial heterogeneity regarding the route of administration, the dosage, the duration of the treatment, and the animal model selected, underlining the urgent need for "coordinated/aligned" preclinical studies laying the foundations for well-defined future clinical trials. The main aim of the present position paper is to critically and concisely consider these key points and open a discussion on the possible "alignment" for future studies, with the goal of validating the full therapeutic potential of this intriguing molecule.

Antioxidant and Neuroprotective Effects of Carnosine: Therapeutic Implications in Neurodegenerative Diseases

Neurodegenerative diseases (NDs) constitute a global challenge to human health and an important social and economic burden worldwide, mainly due to their growing prevalence in an aging population and to their associated disabilities. Despite their differences at the clinical level, NDs share fundamental pathological mechanisms such as abnormal protein deposition, intracellular Ca²⁺ overload, mitochondrial dysfunction, redox homeostasis imbalance and neuroinflammation. Although important progress is being made in deciphering the mechanisms underlying NDs, the availability of effective therapies is still scarce. Carnosine is a natural endogenous molecule that has been extensively studied during the last years due to its promising beneficial effects for human health. It presents multimodal mechanisms of action, being able to exert antioxidant, anti-inflammatory and anti-aggregate activities, among others. Interestingly, most NDs exhibit oxidative and nitrosative stress, protein aggregation and inflammation as molecular hallmarks. In this review, we discuss the neuroprotective functions of carnosine and its implications as a therapeutic strategy in different NDs. We summarize the existing works that study alterations in carnosine metabolism in Alzheimer’s disease and Parkinson’s disease, the two most common NDs. In addition, we review the beneficial effect that carnosine supplementation presents in models of such diseases as well as in aging-related neurodegeneration.

Hybrid thermosensitive-mucoadhesive in situ forming gels for enhanced corneal wound healing effect of L-carnosine

Purpose

Thermosensitive in situ gels have been around for decades but only a few have been translated into ophthalmic pharmaceuticals. The aim of this study was to combine the thermo-gelling polymer poloxamer 407 and mucoadhesive polymers chitosan (CS) and methyl cellulose (MC) for developing effective and long-acting ophthalmic delivery systems for L-carnosine (a natural dipeptide drug) for corneal wound healing.

Methods

The effect of different polymer combinations on parameters like gelation time and temperature, rheological properties, texture, spreading coefficients, mucoadhesion, conjunctival irritation potential, in vitro release, and ex vivo permeation were studied. Healing of corneal epithelium ulcers was investigated in a rabbit’s eye model.

Results

Both gelation time and temperature were significantly dependent on the concentrations of poloxamer 407 and additive polymers (chitosan and methyl cellulose), where it ranged from <10 s to several minutes. Mechanical properties investigated through texture analysis (hardness, adhesiveness, and cohesiveness) were dependent on composition. Promising spreading-ability, mucoadhesion, transcorneal permeation of L-carnosine, high ocular tolerability, and enhanced corneal epithelium wound healing were recorded for poloxamer 407/chitosan systems.

Conclusion

In situ gelling systems comprising combinations of poloxamer-chitosan exhibited superior gelation time and temperature, mucoadhesion, and rheological characteristics suitable for effective long-acting drug delivery systems for corneal wounds.