Dendrobium nobile Lindl. Polysaccharides protect fibroblasts against UVA-induced photoaging via JNK/c-Jun/MMPs pathway

Fucoidan Oligosaccharide Supplementation Relieved Kidney Injury and Modulated Intestinal Homeostasis in D-Galactose-Exposed Rats

Background/Objectives: A fucoidan oligosaccharide (FOS), a potent compound derived from algae, is known for its diverse biological activities, including prebiotic activity, anticancer activity, and antioxidative properties, and has demonstrated supportive therapeutic effects in treating kidney ailments. This study was conducted to explore the protective influence of FOS on kidney damage due to aging induced by D-galactose in Sprague Dawley (SD) rats. Methods: The low-dose FOS group was administered FOS (100 mg/kg) by gavage, and the high-FOS group received FOS (200 mg/kg) by gavage. Results: The findings showed that FOS could effectively mitigate kidney damage and improve the pathological condition of kidney tissues caused by D-gal and enhance kidney function. Intervention with FOS significantly reduced serum creatinine, serum uric acid, and serum urea nitrogen levels, compared to the model group. The protective mechanism of FOS on D-gal-induced kidney injury may be to inhibit oxidative stress and improve impaired mitochondrial function by downregulating the AMPK/ULK1 signaling pathway. FOS could also modulate the expression of mitochondrial autophagy-related proteins (Beclin-1, P62, and LC3II/LC3I), thereby mitigate D-gal-induced excessive mitophagy in the kidney. Furthermore, FOS may protect against kidney injury by preserving intestinal homeostasis. FOS decreased serum lipopolysaccharide levels and enhanced intestinal mucosal barrier function. FOS upregulated the abundances of Bacteroidota, Muribaculaceae, and Lactobacillus, while it decreased the abundances of Firmicutes, NK4A136_group, and Lachnospiraceae_NK4A136_group. FOS supplementation modulated gut microbiota composition, increasing beneficial bacteria and reducing detrimental ones, potentially contributing to improved kidney function. Conclusions: FOS may safeguard against renal injury in D-gal-exposed rats by inhibiting kidney excessive mitophagy, preserving mitochondrial function, and regulating intestinal homeostasis.

Phytocosmetic potential of Blumea balsamifera oil in mitigating UV-induced photoaging: Evidence from cellular and mouse models

ETHNOPHARMACOLOGICAL RELEVANCE

Blumea balsamifera (L.) DC. (BB), the source of Blumea balsamifera oil (BBO), is an aromatic medicinal plant, renowned for its pharmacological properties and its traditional use in Southeast Asian countries such as China, Thailand, Vietnam, Malaysia, and the Philippines for centuries. Traditionally, BB has been used as a raw herbal medicine for treating various skin conditions like eczema, dermatitis, athlete's foot, and wound healing for skin injuries.

AIM OF THE STUDY

This research aimed to explore the inhibitory effects of BBO on skin aging using two models: in vitro analysis with human dermal fibroblasts (HDF) under UVB-induced stress, and in vivo studies on UVA-induced dorsal skin aging in mice. The study sought to uncover the mechanisms behind BBO's anti-aging effects, specifically, its impact on cellular and tissue responses to UV-induced skin aging.

MATERIALS AND METHODS

We applied doses of 10-20 μL/mL of BBO to HDF cells that had been exposed to UVB radiation to simulate skin aging. We measured cell viability, and levels of reactive oxygen species (ROS), SA-β-gal, pro-inflammatory cytokines, and matrix metalloproteinases (MMPs). In addition, we investigated the involvement of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways in mediating the anti-aging effects of BBO. Histopathological and biochemical analyses were conducted in a mouse model to examine the effects of BBO on UV-induced photoaging.

RESULTS

UV exposure accelerated aging, and caused cellular damage and inflammatory responses through ROS-mediated pathways. In HDF cells, BBO treatment countered the UVB-induced senescence, and the recovery of cell viability was correlated to notable reductions in SA-β-gal, ROS, pro-inflammatory cytokines, and MMPs. Mechanistically, the anti-aging effect of BBO was associated with the downregulation of the JNK/NF-κB signaling pathways. In the in vivo mouse model, BBO exhibited protective capabilities against UV-induced photoaging, which were manifested by the enhanced antioxidant enzyme activities and tissue remodeling.

CONCLUSIONS

BBO effectively protects fibroblasts from UV-induced photoaging through the JNK/NF-κB pathway. Recovery from photoaging involves an increase in dermal fibroblasts, alleviation of inflammation, accelerated synthesis of antioxidant enzymes, and slowed degradation of ECM proteins. Overall, BBO enhances the skin's defensive capabilities against oxidative stress, underscoring its potential as a therapeutic agent for oxidative stress-related skin aging.

Role of fibroblast autophagy and proliferation in skin anti-aging

Skin, as the outermost protective barrier of the body, becomes damaged with age and exposure to external stimuli. Dermal fibroblasts age and undergo apoptosis, which decreases collagen, collagen fibers, elastic fibers, hyaluronic acid, etc., leading skin to loss of elasticity and appearance of wrinkles. Skin aging is complex, involving several biological reactions，and various treatment methods are used to treat it. This review focuses on the importance of autophagy and cell proliferation in skin anti-aging, summarizes research progress on skin anti-aging by regulating autophagy and promoting the proliferation of dermal fibroblasts, and discusses future directions on skin anti-aging research.

Protective effects of degraded Bletilla striata polysaccharides against UVB-induced oxidative stress in skin

The Bletilla striata polysaccharides (BSP) extracted through alkali-assisted method exhibit significant antioxidant activity, but its bioaccessibility was inadequate due to its tightly filamentous reticulation structure and high molecular weight. The anti-photoaging and anti-melanogenesis effects of degraded BSP (DBSPs) against UVB-induced oxidative stress on the skin were investigated. The molecular weights of the DBSPs were reduced to 153.94 kDa, 66.96 kDa, and 15.54 kDa from an initial value of 298.82 kDa. The degradation treatment altered the branched chain structure of the DBSPs, while the backbone structure, triple-helix structure, and crystallinity remained. DBSPs with a lower molecular weight exhibit better in vitro antioxidant activity. DBSPs did not show cytotoxicity to HSF cells but inhibited B16F10 cell proliferation. The addition of DBSPs protected HSF and B16F10 cells from oxidative stress and reduced ROS levels, B16F10 melanin content, and B16F10 tyrosinase activity after UVB damage, but DBSP-10 particles were slightly less effective due to aggregation. In contrast, DBSP-5 demonstrated effectiveness in reducing MDA levels in cells stressed by oxidative stress, increased total antioxidant capacity, and inhibited melanogenesis in B16F10, suggesting that DBSP-5 has potential as a topical therapeutic agent for the treatment of skin diseases associated with oxidative stress.

Dendrobium nobile Polysaccharide Attenuates Blue Light-Induced Injury in Retinal Cells and In Vivo in Drosophila

Blue light is the higher-energy region of the visible spectrum. Excessive exposure to blue light is known to induce oxidative stress and is harmful to the eyes. The stems of Dendrobium nobile Lindl. (Orchidaceae), named Jinchaishihu, have long been used in traditional Chinese medicine (TCM) for nourishing yin, clearing heat, and brightening the eyes. The polysaccharide is one of the major components in D. nobile. However, the effect on ocular cells remains unclear. This study aimed to investigate whether the polysaccharide from D. nobile can protect the eyes from blue light-induced injury. A crude (DN-P) and a partially purified polysaccharide (DN-PP) from D. nobile were evaluated for their protective effects on blue light-induced damage in ARPE-19 and 661W cells. The in vivo study investigated the electroretinographic response and the expression of phototransduction-related genes in the retinas of a Drosophila model. The results showed that DN-P and DN-PP could improve blue light-induced damage in ARPE-19 and 661W cells, including cell viability, antioxidant activity, reactive oxygen species (ROS)/superoxide production, and reverse opsin 3 protein expression in a concentration-dependent manner. The in vivo study indicated that DN-P could alleviate eye damage and reverse the expression of phototransduction-related genes, including ninaE, norpA, Gαq, Gβ76C, Gγ30A, TRP, and TRPL, in a dose-dependent manner in blue light-exposed Drosophila. In conclusion, this is the first report demonstrating that D. nobile polysaccharide pretreatment can protect retinal cells and retinal photoreceptors from blue light-induced damage. These results provide supporting evidence for the beneficial potential of D. nobile in preventing blue light-induced eye damage and improving eyesight.

Alleviation of ultraviolet-B radiation-induced photoaging using Saussurea medusa Maxim polysaccharide

Saussurea medusa polysaccharide, the polysaccharide extract of Saussurea medusa Maxim, a traditional Chinese herbal medicine, is used to combat intense ultraviolet radiation, cold, and hypoxia in patients, as well as during drought. This polysaccharide has rich medicinal and ecological values. We aimed to determine whether saussurea medusa polysaccharides can reduce ultraviolet B (UVB)-induced skin photoaging. Seventy-five male Kunming mice were divided into five groups: control, UVB-only, UVB plus vitamin E (VE group), UVB plus saussurea medusa (2 g/kg), and UVB plus saussurea medusa (6 g/kg). The control group was irradiated with normal light, while the other four groups were subcutaneously administered 10 mL/kg/day D-galactose and irradiated with narrow-spectrum UVB for 40 min daily. From day 11, the VE group was administered 0.25 g/kg/day vitamin E, while the saussurea medusa intervention groups were administered 2 and 6 g/kg/day saussurea medusa polysaccharide. After 30 days of continuous administration, treatment with saussurea medusa polysaccharides was found to reduce UVB-induced skin photoaging in mice by elevating the levels of superoxide dismutase, glutathione peroxidase, and hydroxyproline (HYP), while reducing the level of MDA, and inhibiting the EGFR/MEK/ERK/c-Fos pathway. Overall, our findings suggest that treatment with saussurea medusa polysaccharides positively influences skin photoaging.

Dendrobium nobile Lindl ameliorates learning and memory deficits in scopolamine-treated mice

ETHNOPHARMACOLOGICAL RELEVANCE

Dendrobium nobile Lindl (DNL), a valued time-honored herb, possesses immune-boosting and age-delaying properties, has been widely used to treat hyperglycemia and neurological diseases, and is probably a potential drug for improving learning and memory. Scopolamine (Scop), an antagonist for muscarinic receptors, potentially impairing intelligence and memory.

AIM OF THE STUDY

This investigation aimed to assess the efficacy of DNL in alleviating scopolamine-induced cognitive deficits in mice and its mechanisms.

MATERIALS AND METHODS

We utilized the open-field test, novel object recognition test (NOR), and Morris water maze test (MWM) to assess the potential of DNL in ameliorating learning and memory dysfunction caused by scopolamine in mice. Enzyme-linked immunosorbent assay (ELISA) was employed to measure Choline acetyltransferase (ChAT) content and Acetylcholinesterase (AChE) activities in the brain, and oxidative stress-related factors in the serum, including Malondialdehyde (MDA), Superoxide dismutase (SOD), and glutathione (GSH) content.

RESULTS

Scopolamine injection significantly reduced the discrimination index of mice in the NOR test and impaired their performance in the MWM test, as demonstrated by longer escape latency, fewer target crossings, and less time spent in the target quadrant in the MWM. After 25 days of administration, DNL increased the discrimination index of the scopolamine-treated mice in the NOR test. DNL reduced the escape latency in the MWM test in the model mice. DNL increased the target crossing number and the percentage of time spent in the target quadrant in the MWM test. ELISA experiments indicated that DNL decreased the AChE activities, increased the ChAT activities, and modulated oxidative stress makers (GSH, SOD, and MDA) in scopolamine-induced mice.

CONCLUSIONS

DNL may improve the learning and memory in mice treated with scopolamine, possibly by modulating oxidative stress and impaired cholinergic function.

Anticipation and Verification of Dendrobium-Derived Nanovesicles for Skin Wound Healing Targets, Predicated Upon Immune Infiltration and Senescence

Background

Dendrobium, with profound botanical importance, reveals a rich composition of bioactive compounds, including polysaccharides, flavonoids, alkaloids, and diverse amino acids, holding promise for skin regeneration. However, the precise mechanism remains elusive. Seeking a potent natural remedy for wound healing, exocyst vesicles were successfully isolated from Dendrobium.

Aims of the Study

This investigation aimed to employ bioinformatics and in vivo experiments to elucidate target genes of Dendrobium-derived nanovesicles in skin wound healing, focusing on immune infiltration and senescence characteristics.

Materials and Methods

C57 mice experienced facilitated wound healing through Dendrobium-derived nanovesicles (DDNVs). Bioinformatics analysis and GEO database mining identified crucial genes by intersecting immune-related, senescence-related, and PANoptosis-associated genes. The identified genes underwent in vivo validation.

Results

DDNVs remarkably accelerated skin wound healing in C57 mice. Bioinformatics analysis revealed abnormal expression patterns of immune-related, senescence-related, and pan-apoptosis-related genes, highlighting an overexpressed IL-1β and downregulated IL-18 in the model group, Exploration of signaling pathways included IL-17, NF-kappa B, NOD-like receptor, and Toll-like receptor pathways. In vivo experiments confirmed DDNVs' efficacy in suppressing IL-1β expression, enhancing wound healing.

Conclusion

Plant-derived nanovesicles (PDNV) emerged as a natural, reliable, and productive approach to wound healing. DDNVs uptake by mouse skin tissues, labeled with a fluorescent dye, led to enhanced wound healing in C57 mice. Notably, IL-1β overexpression in immune cells and genes played a key role. DDNVs intervention effectively suppressed IL-1β expression, accelerating skin wound tissue repair.

The cGAS-STING pathway: a therapeutic target in diabetes and its complications

Diabetic wound healing (DWH) represents a major complication of diabetes where inflammation is a key impediment to proper healing. The cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) signaling pathway has emerged as a central mediator of inflammatory responses to cell stress and damage. However, the contribution of cGAS-STING activation to impaired healing in DWH remains understudied. In this review, we examine the evidence that cGAS-STING-driven inflammation is a critical factor underlying defective DWH. We summarize studies revealing upregulation of the cGAS-STING pathway in diabetic wounds and discuss how this exacerbates inflammation and senescence and disrupts cellular metabolism to block healing. Partial pharmaceutical inhibition of cGAS-STING has shown promise in damping inflammation and improving DWH in preclinical models. We highlight key knowledge gaps regarding cGAS-STING in DWH, including its relationships with endoplasmic reticulum stress and metal-ion signaling. Elucidating these mechanisms may unveil new therapeutic targets within the cGAS-STING pathway to improve healing outcomes in DWH. This review synthesizes current understanding of how cGAS-STING activation contributes to DWH pathology and proposes future research directions to exploit modulation of this pathway for therapeutic benefit.

Bioactive Compounds for Combating Oxidative Stress in Dermatology

There are extensive studies that confirm the harmful and strong influence of oxidative stress on the skin. The body's response to oxidative stress can vary depending on the type of reactive oxygen species (ROS) or reactive nitrogen species (RNS) and their metabolites, the duration of exposure to oxidative stress and the antioxidant capacity at each tissue level. Numerous skin diseases and pathologies are associated with the excessive production and accumulation of free radicals. title altered Both categories have advantages and disadvantages in terms of skin structures, tolerability, therapeutic performance, ease of application or formulation and economic efficiency. The effect of long-term treatment with antioxidants is evaluated through studies investigating their protective effect and the improvement of some phenomena caused by oxidative stress. This article summarizes the available information on the presence of compounds used in dermatology to combat oxidative stress in the skin. It aims to provide an overview of all the considerations for choosing an antioxidant agent, the topics for further research and the answers sought in order to optimize therapeutic performance.

Research Progress in Skin Aging, Metabolism, and Related Products

In recent years, skin aging has received increasing attention. Many factors affect skin aging, and research has shown that metabolism plays a vital role in skin aging, but there needs to be a more systematic review. This article reviews the interaction between skin metabolism and aging from the perspectives of glucose, protein, and lipid metabolism and explores relevant strategies for skin metabolism regulation. We found that skin aging affects the metabolism of three major substances, which are glucose, protein, and lipids, and the metabolism of the three major substances in the skin also affects the process of skin aging. Some drugs or compounds can regulate the metabolic disorders mentioned above to exert anti-aging effects. Currently, there are a variety of products, but most of them focus on improving skin collagen levels. Skin aging is closely related to metabolism, and they interact with each other. Regulating specific metabolic disorders in the skin is an important anti-aging strategy. Research and development have focused on improving collagen levels, while the regulation of other skin glycosylation and lipid disorders including key membrane or cytoskeleton proteins is relatively rare. Further research and development are expected.

Unripe Carica papaya Fresh Fruit Extract Protects against Methylglyoxal-Mediated Aging in Human Dermal Skin Fibroblasts

The glycolytic metabolite methylglyoxal (MGO) initiates the formation of advanced glycation end products and oxidative stress, leading to cellular senescence and skin aging. This study focuses on the anti-aging properties of unripe Carica papaya L. (UCP) fresh fruit extract on MGO-induced human dermal fibroblast senescence. We pretreated human foreskin fibroblasts with UCP before incubating them with MGO (400 μM) for 72 h. We used the glycation inhibitor aminoguanidine hydrochloride (AG) as the positive control. Senescent fibroblasts were detected using senescence-associated beta-galactosidase activity and collagen type I expression (COL1A1). We investigated the changes in the Akt, JNK/p38 mitogen-activated protein kinase (MAPK), c-Jun, and nuclear factor kappa B (NF-κB) signaling pathways using Western blotting. UCP significantly suppressed MGO-induced senescent fibroblasts (from 20.90±2.00% to 11.78±2.04%) when compared with the baseline level at 7.10±0.90% (P<0.05). While COL1A1 was diminished by 43.35±1.56% (P<0.001) in the MGO-treated fibroblasts, UCP and AG could recover COL1A1 to 63.22±4.78% and 64.39±3.34%, respectively. MGO triggered overactivation of Akt, JNK/p38 MAPK, c-Jun, and NF-κB by 2.10±0.09, 8.10±0.37, 6.60±0.29, 2.18±0.23, and 3.74±0.37 folds, respectively. UCP and AG significantly abolished these changes. Consistently, MGO increased matrix metalloproteinase-1 (MMP-1) levels by 2.58±0.04 folds, which was significantly suppressed by UCP and AG pretreatment to 1.87±0.11 and 1.69±0.07 folds, respectively. In summary, UCP controlled MGO-induced fibroblast senescence by suppressing the JNK/c-Jun/MMP and p38/NF-κB/COL1A1 pathways, similar to the action of the glycation inhibitor AG. Therefore, UCP can be considered a functional fruit for preventing and delaying skin aging.

Protective effect of solanesol in glucose-induced hepatocyte injury: Mechanistic insights on oxidative stress and mitochondrial preservation

Solanesol is a tetra sesquiterpene enol with various biological activities. Modern medical studies have confirmed that solanesol has the function of lipid antioxidation and scavenges free radicals. This study aimed to investigate the protective effect of solanesol against oxidative damage induced by high glucose on human normal hepatocytes (L-02 cells) and its possible mechanism. The results showed that solanesol could effectively improve the decrease of cell viability induced by high glucose, decrease the contents of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and lactate dehydrogenase (LDH) in the extracellular medium, increased the enzyme activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), balanced the level of reactive oxygen species (ROS) in cells, inhibited lipid peroxidation of all kinds of biological membranes, and restored mitochondrial membrane potential (MMP). In addition, Solanesol also inhibited the expression of Keap1, promoted the nuclear translocation of Nrf2 by hydrogen bonding with Nrf2, and activated the expression of downstream antioxidant factors NQO1 and HO-1. Altogether, these findings suggest that solanesol may be a potential protectant against diabetic liver injury.

Dendrobium nobile Lindl Polysaccharides Attenuate UVB-induced Photodamage by Regulating Oxidative Stress, Inflammation and MMPs Expression in Mice Model

Acute ultraviolet B (UVB) irradiation predominantly leads to various skin disorders caused by photodamage. The major causes of UVB-induced photodamage include oxidative stress, inflammatory infiltration and collagen degradation. The aim of the study was to elucidate whether DNP had protective effect on the skin of KM mice when exposed to UVB irradiation. The DNP protective properties to skin appearance and histopathological alterations in KM mice were evaluated by hematoxylin-eosin staining, toluidine blue staining, Gomori staining and Masson's trichrome staining and mast cell staining. In this study, DNP pretreatment promoted the activities of antioxidant enzymes, including superoxide dismutase, catalase and glutathione peroxidase, while decreased malondialdehyde level in UVB-irradiated skin, along with downregulation of proteins expression of matrix metalloproteinases and reduction in the level of the proinflammatory cytokines. Based on these findings, we demonstrated that DNP displayed strong ameliorative effects on UVB-induced acute photodamage for the first time, indicating that it would be a promoting ingredient candidate that could be used in antiphotodamage.

Phenotypic, Physiological, and Molecular Response of Loropetalum chinense var. rubrum under Different Light Quality Treatments Based on Leaf Color Changes

Light quality is a vital environmental signal used to trigger growth and to develop structural differentiation in plants, and it influences morphological, physiological, and biochemical metabolites. In previous studies, different light qualities were found to regulate the synthesis of anthocyanin. However, the mechanism of the synthesis and accumulation of anthocyanins in leaves in response to light quality remains unclear. In this study, the Loropetalum chinense var. rubrum "Xiangnong Fendai" plant was treated with white light (WL), blue light (BL), ultraviolet-A light (UL), and blue light plus ultraviolet-A light (BL + UL), respectively. Under BL, the leaves were described as increasing in redness from "olive green" to "reddish-brown". The chlorophyll, carotenoid, anthocyanin, and total flavonoid content were significantly higher at 7 d than at 0 d. In addition, BL treatment also significantly increased the accumulation of soluble sugar and soluble protein. In contrast to BL, ultraviolet-A light increased the malondialdehyde (MDA) content and the activities of three antioxidant enzymes in the leaves, including catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD), in varying degrees over time. Moreover, we also found that the CRY-like gene, HY5-like gene, BBX-like gene, MYB-like gene, CHS-like gene, DFR-like gene, ANS-like gene, and UFGT-like gene were significantly upregulated. Furthermore, the SOD-like, POD-like, and CAT-like gene expressions related to antioxidase synthesis were found under ultraviolet-A light conditions. In summary, BL is more conducive to reddening the leaves of "Xiangnong Fendai" and will not lead to excessive photooxidation. This provides an effective ecological strategy for light-induced leaf-color changes, thereby promoting the ornamental and economic value of L. chinense var. rubrum.

Efficient production and skincare activity evaluation of schizophyllan, a β-glucan derived from Schizophyllum commune NTU-1

Schizophyllan (SPG), a β-glucan produced by the fungus Schizophyllum commune, possesses a β-(1 → 3)-linked backbone with single β-(1 → 6)-linked glucose side chains at approximately every third residue. In this study, we screened SPG-producing strains of S. commune from different provinces in China. A candidate strain (NTU-1) with a high SPG yield was chosen, and the fermentation conditions were optimized. The optimal carbon and nitrogen sources were sucrose (40 g/L) and yeast extract (20 g/L), respectively. The optimal conditions for pH and temperature were 5.0 and 28 °C, respectively. Inclusion of 0.2 mg/L of 2,4-Dichlorophenoxyacetic acid in the medium further increased the SPG concentration. In a 5-L bioreactor, the fermentation cycle was reduced from the initial seven days to five days, and the concentration of SPG obtained was 21.3 g/L, which is the highest reported to date. In addition, we evaluated the bioactivity of the SPG prepared using strain NTU-1. The results showed that SPG had certain characteristics of anti-oxidation, anti-photoaging, and inhibition of melanin production, making it a promising reagent for skin care.

Photoprotective Effects of Dendrobium nobile Lindl. Polysaccharides against UVB-Induced Oxidative Stress and Apoptosis in HaCaT Cells

Acute ultraviolet (UV)-B radiation is the major external factor causing photodamage. In this study, we aimed to determine the effects of Dendrobium nobile Lindl. polysaccharides (DNPs) on photodamage in HaCaT keratinocytes after UVB irradiation and the underlying mechanisms. We found that DNPs significantly attenuated the decline in the viability and proliferation of HaCaT cells after UVB irradiation. Moreover, DNPs scavenged reactive oxygen species (ROS), improved the activities of endogenous antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase, and reduced the levels of malondialdehyde, while partially attenuating cell cycle arrest, suggesting their antioxidant and anti-apoptotic properties. The mitogen-activated protein kinase (MAPK) pathway was found to be important for the attenuation of UVB-induced photodamage in the HaCaT cells. Furthermore, DNPs exerted cytoprotective effects by downregulating UVB-induced ROS-mediated phosphorylation of MAPKs, including p38, c-Jun N-terminal kinase, and extracellular signal-regulated kinase, and by inhibiting p53 expression as well as the apoptotic cascade response. Therefore, DNPs ameliorated UVB-induced oxidative damage and apoptosis in HaCaT cells via the regulation of MAPKs. Our findings thus highlight the Dendrobium nobile Lindl polysaccharides as promising therapeutic candidates for UVB-induced photodamage.