γ-Mangosteen, an autophagy enhancer, prevents skin-aging via activating KEAP1/NRF2 signaling and downregulating MAPKs/AP-1/NF-κB-mediated MMPs.

BACKGROUND: Mangosteens, a naturally occurring xanthones, found abundantly in mangosteen fruits. The anti-skin aging potential of γ-mangosteen (GM) remains unexplored; therefore, we investigated the UVB-induced anti-skin aging of GM via activation of autophagy. HYPOTHESIS: We hypothesized that GM exerts antioxidant and anti-aging capabilities both in vitro and in vivo through activation of autophagy as well as control of KEAP1/NRF2 signaling and MAPKs/AP-1/NF-κB-mediated MMPs pathways. METHODS: The anti-skin aging effects of GM were studied using HDF cells and a mice model. Various assays, such as DPPH, ABTS, CUPRAC, FRAP, and ROS generation, assessed antioxidant activities. Kits measured antioxidant enzymes, SA-ß-gal staining, collagen, MDA content, si-RNA experiments, and promoter assays. Western blotting evaluated protein levels of c-Jun, c-Fos, p-IκBα/ß, p-NF-κB, MAPK, MMPs, collagenase, elastin, KEAP1, NRF2, HO-1, and autophagy-related proteins. RESULTS: GM exhibited strong antioxidant, collagenase and elastase enzyme inhibition activity surpassing α- and ß-mangosteen. GM competitively inhibited elastase with a Ki value of 29.04 µM. GM orchestrated the KEAP1-NRF2 pathway, enhancing HO-1 expression, and suppressed UVB-induced ROS in HDF cells. NRF2 knockdown compromised GM's antioxidant efficacy, leading to uncontrolled ROS post-UVB. GM bolstered endogenous antioxidants, curbing lipid peroxidation in UVB-exposed HDF cells and BALB/c mice. GM effectively halted UVB-induced cell senescence, and reduced MMP-1/-9, while elevated TIMP-1 levels, augmented COL1A1, ELN, and HAS-2 expression in vitro and in vivo. Additionally, it suppressed UVB-induced MAPKs, AP-1, NF-κB phosphorylation. Pharmacological inhibitors synergistically enhanced GM's anti-skin aging potential. Moreover, GM inhibited UVB-induced mTOR activation, upregulated LC3-II, Atg5, Beclin 1, and reduced p62 in both UVB induced HDF cells and BALB/c mice, while blocking of autophagy successfully halt the GM effects against the UVB-induced increase of cell senescence, degradation of collagen through upregulation of MMP-1, underscoring GM's substantial anti-skin aging impact via autophagy induction in vitro and in vivo. CONCLUSION: Together, GM has potent antioxidant and anti-skin aging ingredients that can be used to formulate skin care products for both the nutraceutical and cosmeceutical industries.

Glycoprotein from Sargassum fusiforme exhibiting anti-inflammatory responses in vitro and in vivo via modulation of TLR4/MyD88 and NF-κB signaling.

This study focuses on the identification and characterization of a glycoprotein from Sargassum fusiforme (Harvey) Setchell (SFGP), as well as investigating its potential anti-inflammatory properties both in vitro and in vivo, along with the underlying mechanism. SDS-PAGE analysis revealed a prominent band with a molecular weight of <10 kDa, consisting of 58.39 % protein and 41.61 % carbohydrates, which was confirmed through glycoprotein staining and Coomassie blue staining. Various analytical techniques, including high-resolution mass spectrometry (HRMS), FTIR, amino acid analysis, and UV-visible spectrometry, provided evidence for the presence of monosaccharides (such as d-glucose and mannose) and 17 amino acids linked by an O-glycopeptide bond. In vitro and in vivo studies were conducted to assess the anti-inflammatory activities of SFGP. The results demonstrated that SFGP effectively attenuated nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expressions in LPS-treated RAW264.7 cells. Moreover, SFGP administration significantly and dose-dependently suppressed TLR4/MyD88 signaling as well as the phosphorylation of MAPKs, IκB, and NF-κB, leading to a reduction in the production of TNF-α, IL-1ß, and IL-6 in LPS-stimulated RAW264.7 cells. Furthermore, the anti-inflammatory efficacy of SFGP was validated in a carrageenan-induced inflammatory mouse model. These findings indicate that SFGP exhibits anti-inflammatory characteristics and has the potential to be utilized as a novel anti-inflammatory agent.

Antioxidant Potential-Rich Betel Leaves (Piper betle L.) Exert Depigmenting Action by Triggering Autophagy and Downregulating MITF/Tyrosinase In Vitro and In Vivo.

Each individual has a unique skin tone based on the types and quantities of melanin pigment, and oxidative stress is a key element in melanogenesis regulation. This research sought to understand the in vitro and in vivo antioxidant and depigmenting properties of betel leaves (Piper betle L.) extract (PBL) and the underlying mechanism. Ethyl acetate fractions of PBL (PBLA) demonstrated excellent phenolic content (342 ± 4.02 mgGAE/g) and strong DPPH, ABTS radicals, and nitric oxide (NO) scavenging activity with an IC50 value of 41.52 ± 1.02 µg/mL, 45.60 ± 0.56 µg/mL, and 51.42 ± 1.25 µg/mL, respectively. Contrarily, ethanolic extract of PBL (PBLE) showed potent mushroom, mice, and human tyrosinase inhibition activity (IC50 = 7.72 ± 0.98 µg/mL, 20.59 ± 0.83 µg/mL and 24.78 ± 0.56 µg/mL, respectively). According to gas chromatography-mass spectrometry, PBL is abundant in caryophyllene, eugenol, O-eugenol, 3-Allyl-6-methoxyphenyl acetate, and chavicol. An in vitro and in vivo investigation showed that PBLE suppressed tyrosinase (Tyr), tyrosinase-related protein-1 and -2 (Trp-1 and Trp-2), and microphthalmia-associated transcription factors (MITF), decreasing the formation of melanin in contrast to the untreated control. PBLE reduced the cyclic adenosine monophosphate (cAMP) response to an element-binding protein (CREB) phosphorylation by preventing the synthesis of cAMP. Additionally, it activates c-Jun N-terminal kinase (JNK) and p38 mitogen-activated protein kinases (p38), destroying Tyr and MITF and avoiding melanin production. Higher levels of microtubule-associated protein-light chain 3 (LC3-II), autophagy-related protein 5 (Atg5), Beclin 1, and lower levels of p62 demonstrate that PBLE exhibits significant anti-melanogenic effects via an autophagy-induction mechanism, both in vitro and in vivo. Additionally, PBLE significantly reduced the amount of lipid peroxidation while increasing the activity of several antioxidant enzymes in vivo, such as catalase, glutathione, superoxide dismutase, and thioredoxin. PBLE can therefore be employed in topical formulations as a potent skin-whitening agent.

Antioxidant, Tyrosinase, α-Glucosidase, and Elastase Enzyme Inhibition Activities of Optimized Unripe Ajwa Date Pulp (Phoenix dactylifera) Extracts by Response Surface Methodology.

The Ajwa date (Phoenix dactylifera L., Arecaceae family) is a popular edible fruit consumed all over the world. The profiling of the polyphenolic compounds of optimized unripe Ajwa date pulp (URADP) extracts is scarce. The aim of this study was to extract polyphenols from URADP as effectively as possible by using response surface methodology (RSM). A central composite design (CCD) was used to optimize the extraction conditions with respect to ethanol concentration, extraction time, and temperature and to achieve the maximum amount of polyphenolic compounds. High-resolution mass spectrometry was used to identify the URADP's polyphenolic compounds. The DPPH-, ABTS-radical scavenging, α-glucosidase, elastase and tyrosinase enzyme inhibition of optimized extracts of URADP was also evaluated. According to RSM, the highest amounts of TPC (24.25 ± 1.02 mgGAE/g) and TFC (23.98 ± 0.65 mgCAE/g) were obtained at 52% ethanol, 81 min time, and 63 °C. Seventy (70) secondary metabolites, including phenolic, flavonoids, fatty acids, and sugar, were discovered using high-resolution mass spectrometry. In addition, twelve (12) new phytoconstituents were identified for the first time in this plant. Optimized URADP extract showed inhibition of DPPH-radical (IC50 = 87.56 mg/mL), ABTS-radical (IC50 = 172.36 mg/mL), α-glucosidase (IC50 = 221.59 mg/mL), elastase (IC50 = 372.25 mg/mL) and tyrosinase (IC50 = 59.53 mg/mL) enzymes. The results revealed a significant amount of phytoconstituents, making it an excellent contender for the pharmaceutical and food industries.

Metabolite Profiling of Microwave-Assisted Sargassum fusiforme Extracts with Improved Antioxidant Activity Using Hybrid Response Surface Methodology and Artificial Neural Networking-Genetic Algorithm.

Sargassum fusiforme (SF) is a popular edible brown macroalga found in Korea, Japan, and China and is known for its health-promoting properties. In this study, we used two sophisticated models to obtain optimized conditions for high antioxidant activity and metabolite profiling using high-resolution mass spectrometry. A four-factor central composite design was used to optimize the microwave-assisted extraction and achieve the maximum antioxidant activities of DPPH (Y1: 28.01 % inhibition), ABTS (Y2: 36.07 % inhibition), TPC (Y3: 43.65 mg GAE/g), and TFC (Y4: 17.67 mg CAE/g), which were achieved under the optimized extraction conditions of X1: 47.67 %, X2: 2.96 min, X3: 139.54 °C, and X4: 600.00 W. Moreover, over 79 secondary metabolites were tentatively identified, of which 12 compounds were reported for the first time in SF, including five phenolic (isopropyl 3-(3,4-dihydroxyphenyl)-2-hydroxypropanoate, 3,4-dihydroxyphenylglycol, scopoletin, caffeic acid 4-sulfate, and cinnamoyl glucose), two flavonoids (4',7-dihydroxyisoflavone and naringenin), three phlorotannins (diphlorethohydroxycarmalol, dibenzodioxin-1,3,6,8-tetraol, and fucophlorethol), and two other compounds (dihydroxyphenylalanine and 5-hydroxybenzofuran-2(3H)-one) being identified for the first time in optimized SF extract. These compounds may also be involved in improving the antioxidant potential of the extract. Therefore, optimized models can provide better estimates and predictive capabilities that would assist in finding new bioactive compounds with improved biological activities that can be further applied at a commercial level.

Terpenoid-Rich Extract of Dillenia indica L. Bark Displays Antidiabetic Action in Insulin-Resistant C2C12 Cells and STZ-Induced Diabetic Mice by Attenuation of Oxidative Stress.

Insulin resistance (IR) plays a key role in the pathogenesis and clinical outcome of patients with multiple diseases and diabetes. In this study, we examined the antidiabetic effects of a terpenoid-rich extract from Dillenia indica L. bark (TRDI) in palmitic acid-induced insulin resistance (PA-IR) in C2C12 myotube and a streptozotocin (STZ)-induced diabetic mice model and explored the possible underlying mechanism. TRDI showed potential DPPH- and ABTS-radical scavenging effects with a half-maximal inhibitory concentration (IC50) value of 9.76 ± 0.50 µg/mL and 17.47 ± 1.31 µg/mL, respectively. Furthermore, TRDI strongly mitigated α-glucosidase activity with an IC50 value of 3.03 ± 1.01 µg/mL, which was 92-fold higher than the positive control, acarbose (IC50 = 279.49 ± µg/mL). TRDI stimulated the insulin receptor substrarte-1 (INS-1), downregulated phosphoinositide-dependent kinase-1 (PDK1) and protein kinase B (Akt) in both normal and PA-IR C2C12 cells as well as in STZ-induced diabetic mice, enhanced glucose transporter 4 (GLUT4) translocation to the plasma membrane (PM), and increased glucose absorption. Furthermore, TRDI administration significantly reduced PA-induced reactive oxygen species (ROS) formation in C2C12 cells and increased the protein level of numerous antioxidant enzymes such as superoxide dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase-1 (GPx-1) and thioredoxin reductase (TrxR) both in vitro and in vivo. Furthermore, TRDI facilitated nuclear factor erythroid 2 related factor 2 (Nrf2) nuclear translocation and increased HO-1 expression in PA-IR C2C12 cells and STZ-induced diabetic mice. However, for the inhibition of Nrf2, TRDI failed to resist the effects of IR. Thus, this study provides new evidence to support the use of TRDI for diabetes treatment.

Lariciresinol Displays Anti-Diabetic Activity through Inhibition of α-Glucosidase and Activation and Enhancement of Insulin Signaling.

SCOPE: The aim of this study is to investigate the antidiabetic effect of lariciresinol (LSR) in C2C12 myotubes and streptozotocin (STZ)-induced diabetic mice. METHODS AND RESULTS: To investigate antidiabetic potential of LSR, α-glucosidase inhibitory assay, molecular docking, glucose uptake assay, western blot assay on antidiabetic biomarkers are performed. STZ-induced diabetic model is used for in vivo study by calculating oral glucose tolerance test, histochemical examination, and glycogen assay. LSR inhibits α-glucosidase activity with an IC50 value of 6.97 ± 0.37 µM and acts as a competitive inhibitor with an inhibitory constant (Ki) value of 0.046 µM. In C2C12 cells, LSR activates insulin signaling leading to glucose transporter 4 (GLUT4) translocation and augmented glucose uptake. Furthermore, in Streptozotocin (STZ)-treated diabetic mice, 3 weeks of oral LSR administration (10 mg kg-1 ) considerably decrease blood glucose levels, while increasing insulin levels in an oral glucose tolerance test, improve pancreatic islet size, increase GLUT4 expression, and significantly enhance insulin signaling in skeletal muscle. LSR treatment also activates glycogen synthase kinase 3ß (GSK-3ß) resulting in improved glycogen content. CONCLUSION: The findings indicate a potential usefulness for oral LSR in the management and prevention of diabetes by enhancing glucose homeostasis.

High Resolution Mass Spectroscopy-Based Secondary Metabolite Profiling of Nymphaea nouchali (Burm. f) Stem Attenuates Oxidative Stress via Regulation of MAPK/Nrf2/HO-1/ROS Pathway.

The secondary metabolites profiling of Nymphaea nouchali stem (NNSE) extract was carried out using a high-resolution mass spectroscopic technique. The antioxidant effects of NNSE, as well as the underlying mechanisms, were also investigated in tert-butyl hydroperoxide (t-BHP)-stimulated oxidative stress in RAW264.7 cells. Tandem mass spectroscopy with (-) negative mode tentatively revealed the presence of 54 secondary metabolites in NNSE. Among them, phenolic acids and flavonoids were predominant. Phenolic acids (brevifolincarboxylic acid, p-coumaroyltartaric acid, niazinin B, lalioside, 3-feruloylquinic acid, and gallic acid-O-rutinoside), flavonoids (elephantorrhizol, apigenin-6-C-galactoside 8-C-arabinoside, and vicenin-2), sialic acid (2-deoxy-2,3-dehydro-N-acetylneuraminic acid), and terpenoid (α-γ-onoceradienedione) were identified in NNSE for the first time. Unbridled reactive oxygen species/nitrogen species (ROS/RNS) and redox imbalances participate in the induction and development of many oxidative stress-linked diseases. The NNSE exhibited significant free radical scavenging capabilities and was also able to reduce t-BHP-induced cellular generation in RAW264.7 cells. The NNSE prevented oxidative stress by inducing the endogenous antioxidant system and the levels of heme oxygenase-1 (HO-1) by upregulating Nrf2 through the modulation of mitogen-activated protein kinases (MAPK), such as phosphorylated p38 and c-Jun N terminal kinase. Collectively, these results indicate that the NNSE exhibits potent effects in preventing oxidative stress-stimulated diseases and disorders through the modulation of the MAPK/Nrf2/HO-1 signaling pathway. Our findings provide new insights into the cytoprotective effects and mechanisms of Nymphaea nouchali stem extract against oxidative stress, which may be a useful remedy for oxidative stress-induced disorders.