Attenuation of protein glycation by functional polyphenolics of dragon fruit (Hylocereus polyrhizus); an in vitro and in silico evaluation

Neuroprotective effect of red dragon fruit extract ameliorates oxidative stress and inflammation in D-galactose-induced aging rat model: biochemical, histological and immunohistochemical study

Aging is a worldwide socioeconomic burden. Cerebellar aging is an enigma contributing to many behavioral aging disorders, hence is its hindering by prophylactic measurements is a crucial geriatric research target. Red dragon fruit (RDF) is a tropical fruit with antioxidant, anti-inflammatory and anti-apoptotic properties. This study aimed to determine the protective effect of RDF extract against cerebellar aging. Thirty-two male albino rats were randomly allocated into 4 groups: Control, RDF, aged and RDF-aged groups. Aged group revealed structural distortion affecting cerebellar layers including a significant (P < 0.05) decrease in Purkinje cells number and decrease in granular cell layer thickness by comparison to the control and RDF groups. Additionally, distorted capillary endothelium, and defective myelination were noticed. Interestingly, cerebellar active caspase-3, iNOS, MDA and 3-NT and serum TNF-α levels significantly increased with aging by comparison to the control and RDF groups (all P < 0.05). Biochemical analysis revealed a significant (P < 0.05) decrease in cerebellar SOD and serum GSH levels in aged rats. RDF extract remarkably ameliorated most of the neuronal degenerative changes with a significant (P < 0.05) increase in Purkinje cells numbers, and granular cell layer thickness by comparison to the aged group. Furthermore, it resulted in a significant (P < 0.05) decrease in cerebellum expression of active caspase-3, iNOS, MDA, 3-NT, and serum TNF-α levels associated with a significant (P < 0.05) increase in cerebellar SOD and serum GSH levels by comparison to the aged group. To the best of our knowledge this is the first study showing a neuroprotective effect for RDF against cerebellar aging. RDF might be effective in attenuation of age-induced cerebellar degenerative changes through its anti-apoptotic, antioxidant and anti-inflammatory effects.

Nutritional Value and Therapeutic Benefits of Dragon Fruit: A Comprehensive Review with Implications for Establishing Australian Industry Standards

Dragon fruit, which is native to northern South America and Mexico, has become a significant crop in tropical and subtropical regions worldwide, including Vietnam, China, and Australia. The fruit (Hylocereus spp.) is rich in various bioactive phytochemical compounds, including phenolic acids, flavonoids, and pigments such as betalains and anthocyanins, which contribute to its antioxidant, anti-inflammatory, and anti-microbial properties. This comprehensive review introduces the origin, classification, and global production of dragon fruit, with a particular focus on its bioactive phytochemicals and therapeutic potential. Additionally, it critically evaluates the current industry standards for fresh dragon fruit production across key producing countries. While these standards primarily focus on quality, classification, and grading criteria, they lack focus on parameters related to the fruit's bioactive content. The absence of established quality standards for fresh produce in the Australian dragon fruit industry presents a unique opportunity to develop guidelines that align with both international benchmarks and the therapeutic potential of the fruit. By addressing this gap, this review can potentially help Australia to position its dragon fruit industry to achieve greater consistency, competitiveness, and consumer appeal. As the demand for functional foods continues to rise, aligning Australian production practices with global standards becomes critical to meeting domestic market expectations. This review provides a comprehensive understanding of dragon fruit's nutritional and therapeutic significance and highlights its potential role in establishing a robust standard for the Australian dragon fruit industry. A review of global industry standards reveled that Australian standard could incorporate classifications of dragon fruits, including external factors like appearance, size, and defect tolerance. Future research is needed to prioritize understanding of the impact of cultivation practices and environmental factors on the bioactive composition of dragon fruit, enabling the development of best practices for growers. Additionally, further studies are needed to evaluate the therapeutic effects of these bioactive properties through clinical trials, particularly their potential in preventing chronic diseases. The advancement of analytical methods for quantifying bioactive compounds will provide deeper insights into their health benefits and support the establishment of bioactive-oriented industry standards. Moreover, investigations of post-harvest handling and processing techniques could optimize the preservation of these valuable compounds, enhancing dragon fruit's role as a functional food.

Deciphering the inhibitory mechanisms of betanin and phyllocactin from Hylocereus polyrhizus peel on protein glycation, with insights into their application in bread

Protein glycation closely intertwines with the pathogenesis of various diseases, sparking a growing interest in exploring natural antiglycation agents. Herein, high-purity betacyanins (betanin and phyllocactin) derived from Hylocereus polyrhizus peel were studied for their antiglycation potential using an in vitro bovine serum albumin (BSA)-glucose model. Notably, betacyanins outperformed aminoguanidine, a recognized antiglycation agent, in inhibiting glycation product formation across different stages, especially advanced glycation end-products (AGEs). Interestingly, phyllocactin displayed stronger antiglycation activity than betanin. Subsequent mechanistic studies employing molecular docking analysis and fluorescence quenching assay unveiled that betacyanins interact with BSA endothermically and spontaneously, with hydrophobic forces playing a dominant role. Remarkably, phyllocactin demonstrated higher binding affinity and stability to BSA than betanin. Furthermore, the incorporation of betacyanins into bread dose-dependently suppressed AGEs formation during baking and shows promise for inhibiting in vivo glycation process post-consumption. Overall, this study highlights the substantial potential of betacyanins as natural antiglycation agents.

Luteolin: A promising multifunctional natural flavonoid for human diseases

Natural products are closely associated with human health. Luteolin (LUT), a flavonoid polyphenolic compound, is widely found in fruits, vegetables, flowers, and herbs. It is noteworthy that LUT exhibits a variety of beneficial pharmacological properties and holds significant potential for clinical applications, particularly in antitumor, anti-convulsion, diabetes control, anti-inflammatory, neuroprotection, anti-oxidation, anti-cardiovascular, and other aspects. The potential mechanism of action has been partially elucidated, including the mediation of NF-κB, toll-like receptor, MAPK, Wnt/β-catenin, PI3K/Akt, AMPK/mTOR, and Nrf-2, among others. The review that aimed to comprehensively consolidate essential information on natural sources, pharmacological effects, therapeutic and preventive potential, as well as potential mechanisms of LUT. The objective is to establish a theoretical basis for the continued development and application of LUT.

In Vitro and Molecular Docking Studies of Antiglycation Potential of Phenolic Compounds in Date Palm (Phoenix dactylifera L.) Fruit: Exploring Local Varieties in the Food Industry

The Moroccan date-growing sector is rich in a wide diversity of varieties but faces major challenges, notably the undervaluation of certain varieties intended mainly for animal feed. In this study, our objective was to evaluate the antiglycation activity of four date varieties, including three low-market-value varieties and one high-market-value variety, harvested during two seasons (2021 and 2022). In addition, to improve our knowledge of the antiglycation potential, molecular docking analyses were carried out. The results of the antiglycation activity of the date extracts showed strong activity, particularly for the ‘Khalt Khal’ variety, which showed a 50% inhibition concentration (IC50) of 1.83 mg/mL and 2 mg/mL in 2021 and 2022, respectively. In addition, the molecular docking analysis also showed the possible link between the bioactive compounds identified and their mechanisms of action. Our findings suggest new evidence for the antiglycation properties of the bioactive compounds present in dates. These results suggest the use of these varieties as a source of bioactive molecules or as a food additive. This could make it possible to create medicines or food products with a high commercial value using dates, which could help to treat the complications associated with glycation.

Pitahaya (Hylocereus ocamponis)-Peel and -Flesh Flour Obtained from Fruit Co-Products-Assessment of Chemical, Techno-Functional and In Vitro Antioxidant Properties

The aim of this work was to assess the chemical composition and physico-chemical, techno-functional, and in vitro antioxidant properties of flours obtained from the peel and flesh of pitahaya (Hylocereus ocamponis) to determine their potential for use as ingredients for food enrichment. The chemical composition, including total betalains, mineral content, and polyphenolic profile, was determined. The techno-functional properties (water holding, oil holding, and swelling capacities) were also evaluated. For the antioxidant capacity, four different methodologies, namely ferrous ion-chelating ability assay, ferric-reducing antioxidant power assay; 1,1-Diphenyl-2-picrylhydrazyl radical scavenging ability assay, and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical assay, were used. Pitahaya-peel flour had higher values for protein (6.72 g/100 g), ash (11.63 g/100 g), and dietary fiber 56.56 g/100 g) than pitahaya-flesh flour, with values of 6.06, 3.63, and 8.22 g/100 g for protein, ash, and dietary fiber, respectively. In the same way, pitahaya peel showed a higher content of minerals, betalains, and polyphenolic compounds than pitahaya-flesh flour, with potassium (4.43 g/100 g), catechin (25.85 mg/g), quercetin-3-rhamnoside (11.66 mg/g) and myricetrin (12.10 mg/g) as principal compounds found in the peel. Again, pitahaya-peel flour showed better techno-functional and antioxidant properties than pitahaya-flesh flour. The results obtained suggest that the flours obtained from the peel and pulp of pitahaya (H. ocamponis) constitute a potential material to be utilized as an ingredient in the food industry due to the high content of bioactive compounds such as betalains, phenolic acids, and flavonoids, with notable antioxidant capacity.

The binding mechanism of oat phenolic acid to whey protein and its inhibition mechanism against AGEs as revealed using spectroscopy, chromatography and molecular docking

Heat sterilization of dairy products can promote the formation of advanced glycation end products (AGEs), protein oxidation products (POPs) and α-dicarbonyl compounds, which have a significant influence on health due to the close association of these products with diabetes complications. In this study, eight oat phenolic acids were first analyzed for their inhibitory effect against AGEs formation. Due to their strong inhibitory effects and structural differences, caffeic acid (CA) and gallic acid (GA) were further selected to assess their anti-glycosylation mechanisms using spectroscopy, chromatography and molecular docking. CA/GA reduced the production of total AGEs and POPs in various bovine milk simulation models and protected whey proteins from structural modifications, oxidation, and cross-linking. Comparative analyses showed a structure-effect relationship between CA/GA and AGEs inhibition. Oat phenolic acids against AGEs and POPs might be related to the unique bonding of key amino acid residues in whey proteins, the inhibitory role of early fructosamine and the trapping of reactive α-dicarbonyl groups to form adducts. In conclusion, oat phenolic acids might present a promising dietary strategy to alleviate AGEs production and glycation of proteins in dairy products upon storage.

Inhibitory effect of Ginkgo biloba seeds peptides on methylglyoxal-induced glycations

The aim of this study was to investigate the antiglycation activity and mechanism of two identified peptides, Valine-Valine-Phenylalanine-Proline-Glycine-Cysteine-Proline-Glutamic acid (VVFPGCPE) and Serine-Valine-Aspartic acid-Aspartic acid-Proline-Arginine-Threonine-Lysine (SVDDPRTL), from Ginkgo biloba seeds protein hydrolysates. Both VVFPGCPE and SVDDPRTL were efficient in bovine serum albumin (BSA)-methylglyoxal (MGO) model to inhibit BSA glycation, while VVFPGCPE showed higher antiglycation activity than SVDDPRTL. In antioxidant assays, VVFPGCPE scavenged more hydroxyl and super anion radicals, and chelated more Fe²⁺. Moreover, VVFPGCPE was more efficient in alleviating glycoxidation since it retained higher content of tryptophan and reduced dityrosine and kynurenine generation. Compared with SVDDPRTL, VVFPGCPE showed better performance in inhibiting protein aggregation and amyloid-like fibrillation formation. Therefore, VVFPGCPE was selected for further mechanism study. The circular dichroism analysis suggested VVFPGCPE could preserve α-helix structure and stabilize protein structure. The MGO trapping assay indicated VVFPGCPE (5 mg/mL) could capture 66.25% MGO within 24 h, and the mass spectrometry revealed VVFPGCPE could trap MGO by forming VVFPGCPE-mono-MGO adducts. Besides, molecular simulations suggested VVFPGCPE could interact with key glycation residues, arginine and lysine residues, of BSA mainly through van der Waals and hydrogen bonds. This study might supply a theoretical basis for the development of VVFPGCPE as an effective antiglycation agent.

Anti-Inflammatory, Antioxidant, and Other Health Effects of Dragon Fruit and Potential Delivery Systems for Its Bioactive Compounds

Dragon fruit (Hylocereus genus) has the potential for the prevention of diseases associated with inflammatory and oxidative processes. We aimed to comprehensively review dragon fruit health effects, economic importance, and possible use in delivery systems. Pubmed, Embase, and Google Scholar were searched, and PRISMA (Preferred Reporting Items for a Systematic Review and Meta-Analysis) guidelines were followed. Studies have shown that pitaya can exert several benefits in conditions such as diabetes, dyslipidemia, metabolic syndrome, cardiovascular diseases, and cancer due to the presence of bioactive compounds that may include vitamins, potassium, betacyanin, p-coumaric acid, vanillic acid, and gallic acid. Moreover, pitaya has the potential to be used in food and nutraceutical products as functional ingredients, natural colorants, ecologically correct and active packaging, edible films, preparation of photoprotective products, and additives. Besides the importance of dragon fruit as a source of bioactive compounds, the bioavailability is low. The development of delivery systems such as gold nanoparticles with these compounds can be an alternative to reach target tissues.

Inhibitory mechanisms of polyphenols on heme protein-mediated lipid oxidation in muscle food: New insights and advances

Lipid oxidation is a major cause of quality deterioration that decreases the shelf-life of muscle-based foods (red meat, poultry, and fish), in which heme proteins, particularly hemoglobin and myoglobin, are the primary pro-oxidants. Due to increasing consumer concerns over synthetic chemicals, extensive research has been carried out on natural antioxidants, especially plant polyphenols. The conventional opinion suggests that polyphenols inhibit lipid oxidation of muscle foods primarily owing to their strong hydrogen-donating and transition metal-chelating activities. Recent developments in analytical techniques (e.g., protein crystallography, nuclear magnetic resonance spectroscopy, fluorescence anisotropy, and molecular docking simulation) allow deeper understanding of the molecular interaction of polyphenols with heme proteins, phospholipid membrane, reactive oxygen species, and reactive carbonyl species; hence, novel hypotheses regarding their antioxidant mechanisms have been formulated. In this review, we summarize five direct and three indirect pathways by which polyphenols inhibit heme protein-mediated lipid oxidation in muscle foods. We also discuss the relation between chemical structures and functions of polyphenols as antioxidants.

Phytochemicals and anti-tyrosinase activities of Paeonia ostii leaves and roots

Tree peony (sect. Moutan) is a kind of Traditional Chinese Medicine and ornamental plant, which has been widely cultivated and utilized for thousands of years. To further study the active components of Paeonia ostii (Moutan, Fengdan), six fractions (soluble free (F), soluble esterification, soluble glycosylation, insoluble bound, insoluble esterification and insoluble glycosylation) were extracted from the leaves and roots by alkaline and acid treatment for the first time. Twenty-one typical compounds were identified and quantified by HPLC-MS. The results showed that total phenolic content (TPC) in peony roots (PR) and peony leaves (PL) were as high as 125.48 and 280.38 mg GAE·g^-1 dw, which maximizes the extraction efficiency of phenolic compounds, especially leaves, compared with the conventional method. PR-F and PL-F had the highest TPC, antioxidant and anti-tyrosinase activities. Paeoniflorin was the main compounds in PL and PR. It and pentagalloylglucose (PGG) almost reached the anti-tyrosinase level of kojic acid, but they showed different inhibitory mechanisms by molecular docking. On the whole, PR-F, PL-F, PGG and paeoniflorin might be potential for skin whitening products.

Phenolics from Chrozophora oblongifolia Aerial Parts as Inhibitors of α-Glucosidases and Advanced Glycation End Products: In-Vitro Assessment, Molecular Docking and Dynamics Studies

Simple Summary

The chemical investigation of Chrozophora oblongifolia aerial parts resulted in the isolation of five phenolic compounds. The isolated metabolites were tested for their antioxidant and advanced glycation end-products (AGEs) formation, α-glucosidase, and lipase inhibitory activities. 1,3,6-Trigalloyl glucose exhibited the highest activity as an antioxidant and AGEs inhibitor as well as an α-glucosidase inhibitor. It showed promising binding affinity and stability towards the human intestinal maltase-glucoamylase α-glucosidases, as revealed through coupled molecular docking and dynamics studies that could encourage the utilization of this compound in the management of diabetes and its complications.

Abstract

Modern life is associated with low physical activity that leads to the accumulation of fats, gaining more weight, and obesity. Accumulation of fat in the abdomen region contributes to diabetes via insulin resistance and hyperglycemia. Polyphenols are major plant constituents that exert antidiabetic activity through different mechanisms, including radicle scavenging activity, regulation of glucose uptake, and inhibition of fat and polysaccharide hydrolysis in addition to their inhibitory role regarding the formation of advanced glycation end products (AGEs). Chemical investigation of C. oblongifolia aerial parts resulted in the isolation of five major compounds: apeginin-7-O-β-D-glucoside (1), quercetin-3-O-β-D-glucuronic acid (2), quercetin-3-O-β-D-galacturonic acid (3), rutin (4), and 1,3,6-trigalloyl glucose (5). The isolated compounds were tested for their antioxidant and AGEs formation, α-glucosidase, and lipase inhibitory activities. Compound 5 revealed the highest antioxidant and AGEs inhibitory activity in bovine serum albumin (BSA)-methylglyoxal, BSA-fructose, and arginine-methylglyoxal models. Moreover, it exhibited a potent inhibitory profile on Saccharomyces cerevisiae α-glucosidases compared to the positive control, acarbose. Compound (5) further depicted promising binding affinity and stability towards the human intestinal maltase-glucoamylase α-glucosidases, which is a diabetes-related therapeutic target, through coupled molecular docking and dynamics studies. The obtained results encourage the usage of 1,3,6-trigalloyl glucose in the management of diabetes and its complications. However, detailed in-vivo studies for this compound should be performed.

High Hemoglobin Glycation Index Is Associated With Telomere Attrition Independent of HbA1c, Mediated by TNFα

CONTEXT

The hemoglobin glycation index (HGI) is correlated with metabolic diseases and inflammation. Whether the HGI is associated with the aging process and how inflammation and oxidative stress affect the relationship remain unclear.

OBJECTIVE

We aimed to analyze links between the HGI and aging biomarkers, and to explore a potential role of inflammation and oxidative stress in the correlations.

METHODS

A cross-sectional study of 434 subjects with different glucose intolerances in a rural community was enrolled. The HGI was calculated as the difference between the measured and predicted hemoglobin A1c (HbA1c). The population was categorized into tertiles of the HGI. Telomere length (LTL) and mitochondrial DNA copy number (mtDNAcn) determined by polymerase chain reaction assay. Tumor necrosis factor (TNF) α and interleukin (IL) 6, 8-oxo-2'-deoxyguanosine (8-oxo-dG), superoxide dismutase (SOD) activities, and glutathione reductase (GR) were measured.

RESULTS

Participants in the high HGI group were older and reported a shorter LTL, higher levels of TNFα, SOD activities, and HbA1c. Correlation analyses demonstrated that HGI was correlated with LTL (r = -0.25, P < .001) and TNFα (r = 0.19, P < .001) regardless of HbA1c levels. No relationship was found between HGI and mtDNAcn. HGI (β = -0.238, 95% CI -0.430, -0.046, P = .015) and TNFα (β = -0.02, 95% CI -0.030, -0.014, P < .001) were proved to be correlated with LTL independently, using multiple linear regression analysis. Ordinal logistic regression models showed that compared with subjects the high HGI group, the possibilities of a higher-level LTL was 5.29-fold in the low HGI group (OR 5.29, 95% CI (2.45, 11.41), P < .001), 2.41-fold in the moderate HGI group (OR 2.41, 95% CI 1.35, 4.30, P = .003) after controlling for confounding variables. Mediation analyses indicated that TNFα accounted for 30.39% of the effects of the HGI on LTL.

CONCLUSION

HGI was negatively related to telomere attrition, independent of HbA1c. TNFα acted as a mediator of the relationship between HGI and LTL.

Medicinal plants used against hepatic disorders in Bangladesh: A comprehensive review

ETHNOPHARMACOLOGICAL RELEVANCE

Liver disease is a major cause of illness and death worldwide which accounts for approximately 2 million deaths per year worldwide, 1 million due to complications of cirrhosis and 1 million due to viral hepatitis and hepatocellular carcinoma. That's why it is seeking the researchers' attention to find out the effective treatment strategies. Phytochemicals from natural resources are the main leads for the development of noble hepatoprotective drugs. The majority of the natural sources whose active compounds are currently employed actually have an ethnomedical use. Ethnopharmacological research is essential for the development of these bioactive compounds. These studies not only provide scientific evidence on medicinal plants utilized for particular therapeutic purposes, but they also ensure cultural heritage preservation. Plenty of experimental studies have been well-documented that the ethnomedicinal plants are of therapeutics' interest for the advanced pharmacological intervention in terms of hepatic disorders.

AIM OF THE STUDY

This study summarizes the processes of hepatotoxicity induced by various toxins and explores identified hepatoprotective plants and their phytoconstituents, which can guide the extraction of novel phytochemical constituents from plants to treat liver injury. This review aimed to summarize the hepatoprotective activity of Bangladeshi medicinal plants where the bioactive compounds may be leads for the drug discovery in future.

MATERIALS AND METHODS

Literature searches in electronic databases, such as Web of Science, Science Direct, SpringerLink, PubMed, Google Scholar, Semantic Scholar, Scopus, BanglaJOL, and so on, were performed using the keywords 'Bangladesh', 'ethnomedicinal plants', 'Hepatoprotective agents' as for primary searches, and secondary search terms were used as follows, either alone or in combination: traditional medicine, medicinal plants, folk medicine, liver, hepatitis, therapeutic uses, and anti-inflammatory. Besides, several books, including the book entitled "Medicinal plants of Bangladesh: chemical constituents and uses" authored by Abdul Ghani, were carefully considered, which contained pharmacological properties and phytoconstituents of many medicinal plants growing and traditionally available in Bangladesh. Among them, the most promising plant species with their latest therapeutic effects against hepatic disorders were deeply considered in this review.

RESULTS

The results of this study revealed that in most cases, therapy using plant extracts stabilized altered hepatic biochemical markers induced by hepatotoxins. Initially, we investigated 32 plant species for hepatoprotective activity, however after extensive literature searching; we observed that 20 plants offer good pharmacological evidence of hepatoprotective function. Consequently, most bioactive compounds derived from the herbs including berberine, thymoquinone, andrographolide, ursolic acid, luteolin, naringenin, genistein, quercetin, troxerutin, morin, epigallocatechin-3-gallate, chlorogenic acid, emodin, curcumin, resveratrol, capsaicin, ellagic acid, etc. are appeared to be effective against hepatic disorders.

CONCLUSIONS

Flavonoids, phenolic acids, monoterpenoids, diterpenoids, triterpenoids, alkaloids, chromenes, capsaicinoids, curcuminoids, and anthraquinones are among the phytoconstituents were appraised to have hepatoprotective activities. All the actions displayed by these ethnomedicinal plants could make them serve as leads in the formulation of drugs with higher efficacy to treat hepatic disorders.

Luteolin Improves Perivascular Adipose Tissue Profile and Vascular Dysfunction in Goto-Kakizaki Rats

We investigated the effects of luteolin on metabolism, vascular reactivity, and perivascular adipose tissue (PVAT) in nonobese type 2 diabetes mellitus animal model, Goto-Kakizaki (GK) rats.

METHODS

Wistar and GK rats were divided in two groups: (1) control groups treated with vehicle; (2) groups treated with luteolin (10 mg/kg/day, for 2 months). Several metabolic parameters such as adiposity index, lipid profile, fasting glucose levels, glucose and insulin tolerance tests were determined. Endothelial function and contraction studies were performed in aortas with (PVAT+) or without (PVAT-) periaortic adipose tissue. We also studied vascular oxidative stress, glycation and assessed CRP, CCL2, and nitrotyrosine levels in PVAT.

RESULTS

Endothelial function was impaired in diabetic GK rats (47% (GK - PVAT) and 65% (GK + PVAT) inhibition of maximal endothelial dependent relaxation) and significantly improved by luteolin treatment (29% (GK - PVAT) and 22% (GK + PVAT) inhibition of maximal endothelial dependent relaxation, p < 0.01). Vascular oxidative stress and advanced glycation end-products' levels were increased in aortic rings (~2-fold, p < 0.05) of diabetic rats and significantly improved by luteolin treatment (to levels not significantly different from controls). Periaortic adipose tissue anti-contractile action was significantly rescued with luteolin administration (p < 0.001). In addition, luteolin treatment significantly recovered proinflammatory and pro-oxidant PVAT phenotype, and improved systemic and metabolic parameters in GK rats.

CONCLUSIONS

Luteolin ameliorates endothelial dysfunction in type 2 diabetes and exhibits therapeutic potential for the treatment of vascular complications associated with type 2 diabetes.

Bioactive Compounds from Ephedra fragilis: Extraction Optimization, Chemical Characterization, Antioxidant and AntiGlycation Activities

Response surface methodology (RSM) with a Box-Behnken design (BBD) was used to optimize the extraction of bioactive compounds from Ephedra fragilis. The results suggested that extraction with 61.93% ethanol at 44.43 °C for 15.84 h was the best solution for this combination of variables. The crude ethanol extract (CEE) obtained under optimum extraction conditions was sequentially fractionated with solvents of increasing polarity. The content of total phenolic (TP) and total flavonoid (TF) as well as the antioxidant and antiglycation activities were measured. The phytochemical fingerprint profile of the fraction with the highest activity was characterized by using RP-HPLC. The ethyl acetate fraction (EAF) had the highest TP and TF contents and exhibited the most potent antioxidant and antiglycation activities. The Pearson correlation analysis results showed that TP and TF contents were highly significantly correlated with the antioxidant and antiglycation activities. Totally, six compounds were identified in the EAF of E. fragilis, including four phenolic acids and two flavonoids. Additionally, molecular docking analysis also showed the possible connection between identified bioactive compounds and their mechanisms of action. Our results suggest new evidence on the antioxidant and antiglycation activities of E. fragilis bioactive compounds that may be applied in the treatment and prevention of aging and glycation-associated complications.

Antioxidant activities of underexplored Chinese medicinal plant parts and their effect against high glucose-induced modulation of fibronectin expression

Diabetes has been a long-standing disorder and its management has been challenging various medical and research experts for several decades because of its complex causative factors and pathophysiological processes leading to complications. Medicinal plants have been explored in several countries and traditional Chinese medicine is one of the well-recognized alternative treatment methods. In this study, we have chosen some of the underexplored plant parts of Chinese medicinal herbs and analyzed their antioxidant activity and ability to modulate the expression of fibronectin during high glucose conditions. Extraction of the plant materials with different solvent led to 17 extracts and among which, 3 extracts (2, 12 & 17) were observed to render more than 50 μg/ml vitamin C equivalents of DPPH free radical scavenging ability and 2 of them (2 & 17) showed more than 25 μg/ml of vitamin C equivalents of ferric ion reducing power. Based on the antioxidant activity and comparison of their total phenolic content, we used extracts 2 & 17 to check their effect on fibronectin expression in MES-13 cells under high sugar conditions. We observed that both extracts showed a significant reduction of fibronectin expression compared to untreated cells with high glucose levels. The expression was much lesser than the normal untreated, normal sugar supplemented cells and this was not observed in vitamin C supplemented cells. In conclusion, crude extracts containing a group of phenolic compounds have shown significant effects against fibronectin expression leading to reduced ECM deposition and tissue fibrosis. Further exploration might provide insights into the exact mechanism and checkpoints of the extract that can successfully reduce diabetes-induced renal complications.

Evaluation of the anti-rheumatic properties of thymol using carbon dots as nanocarriers on FCA induced arthritic rats

Rheumatoid Arthritis (RA) is an autoimmune disease that commences as inflammation and progressively destroys the articular joint. In this study, we assess the anti-rheumatic potential of the monoterpenoid class of thymol conjugated with Carbon Dots (CDs). Waste biomass in the form of dried rose petals was chosen as a precursor for the synthesis of CDs via a one-step hydrothermal bottom-up methodology. The prepared CDs exhibited absorption in the near-visible region, and unique excitation-dependent emission behaviour was confirmed from UV-Visible and fluorescence measurements. The surface morphology of CDs was confirmed by SEM and HR-TEM analysis to be quasi-spherical particles with an average size of ∼5-6 nm. The presence of various functional moieties (hydroxyl, carbonyl, and amino) was confirmed via FT-IR measurement. The graphitization of CDs was confirmed by the D and G bands for sp2 and sp3 hybridization, respectively, through Raman analysis. Esterification methodology was adopted to prepare the CDs-thymol conjugate and confirmed via FT-IR analysis. CDs play the role of a nanocarrier for thymol, an anti-arthritic agent. The bioactive compound of thymol showed potent anti-arthritic activity against RA targets through in silico docking studies. Further, the in vivo studies revealed that CDs-thymol conjugates (10 mg per kg body weight) showed a significant reduction in rat paw volume along with reduced levels of RF and CRP (2.23 ± 0.42 IU ml-1 and 16.96 ± 0.22 mg ml-1) when compared to the disease control rats. X-ray radiography and ultrasonic imaging revealed less bone destruction, joint derangement, and swelling in arthritis-induced Wistar rats. They could also potentially improve the Hb (14.14 ± 0.19), RBC (6.01 ± 0.11), PCV (6.01 ± 0.11) levels and elevate the status of antioxidant enzymes (GPx, SOD, MDA), and the activity was comparable to the standard drug, ibuprofen (10 mg kg-1), suggesting that the CDs-thymol conjugate at 10 mg kg-1 could act as a strong anti-arthritic agent. This work is evidence for the utilization of waste biomass as a value-added product such as a nanocarrier for biomedical applications.