Xuelan Gu

• Doctor of Philosophy
• Lead Scientist at Unilever R&D Center

Background Pollutant particles can penetrate and accumulate in skin, leading to excessive oxidative stress, inflammation, and skin disorders. Reduced glutathione (GSH) is considered as “the master antioxidant” and major detoxification agent. Aims To characterize the metabolomic changes of skin keratinocytes under the pollutant benzo[a]pyrene (BaP)...

The epidermis acts as the body’s primary defense, relying on components like lipids, HA and GSH for skin barrier function, hydration and resistance to oxidative stress. However, limitations in the topical application of these biomolecules call for novel approaches. This study investigates the efficacy of Pro-GHL, a blend of free fatty acids, acetyl...

The skin acts as the first line of defense against various environmental stressors, such as solar ultraviolet radiation, visible light, pollution particles and ozone. Simultaneous exposure to different stressors is common in everyday life but has been less studied than exposure to single stressors. Herein, the combined effects of a chemical polluta...

Background Facial aging, cognitive impairment, and dementia are all age-related conditions. However, the temporal relation between facial age and future risk of dementia was not systematically examined. Objectives To investigate the relationship between facial age (both subjective/perceived and objective) and cognitive impairment and/or dementia r...

Background Although glutathione (GSH) has long been considered a master antioxidant, poor stability and bioavailability limit its application in skin protection. To overcome the challenges, Unilever R&D formulated a Glutathione Amino acid Precursors blend (named GAP) to boost GSH de novo synthesis. Objective Determine whether GAP can boost GSH lev...

Background UV radiation exposure causes skin irritation, erythema, darkening and barrier disruption by inducing oxidative stress and inflammation. Glutathione, a master antioxidant, plays an important role in the antioxidant defence network of the skin. Objective This study aimed to assess the in vitro protective effects of the glutathione amino a...

Objectives: Cohort and epidemiology studies have previously revealed potential associations between air pollution exposure and acne vulgaris. However, the molecular mechanisms that drive these associations are not currently well understood. In this study, we compared the molecular signatures of acne and PM2.5-exposed skin to infer whether common un...

Objectives: We evaluated the role of 12-hydroxystearic acid (12HSA) in upregulating skin antimicrobial peptides (AMPs) in in vitro and ex vivo assays, and 12HSA provides long-lasting germ protection in vivo through a handwash formulation. Methods: In vitro assays were performed by treating skin cells, maintained in cell-culture media, with 12HSA. A...

Objectives: Pollution exposure is associated with several dermatological conditions including acne, atopic dermatitis, and psoriasis. Antimicrobial peptides (AMPs) are key effectors of innate defense, and some AMPs are involved in inflammatory skin conditions. In this study, we aimed to characterize expression changes of human AMPs under different...

Objectives: Scalp hair has the greatest number of hairs (typically 1-5) per follicular unit but is also the most susceptible body site to hair loss with age. Hence, we set-out to determine the degree to which scalp hair parameters change with age in women and men, any sex differences thereof and whether hair loss is random across follicular units....

Omic-based technologies are of particular interest and importance for hazard identification and health risk characterization of chemicals. Their application in the new approach methodologies (NAMs) anchored on cellular toxicity pathways is based on the premise that any apical health endpoint change must be underpinned by some alterations at the omi...

Omic-based technologies are of particular interest and importance for non-animal chemical hazard and risk characterization based on the premise that any apical endpoint change must be underpinned by some alterations measured at the omic levels. In this work we studied cellular responses to caffeine and coumarin by generating and integrating multi-o...

Skin, as the outmost layer of human body, is frequently exposed to environmental stressors including pollutants and ultraviolet (UV), which could lead to skin disorders. Generally, skin response process to ultraviolet B (UVB) irradiation is a nonlinear dynamic process, with unknown underlying molecular mechanism of critical transition. Here, the la...

Inhibition of glucose uptake in the intestine through sodium-dependent glucose transporter 1 (SGLT1) or glucose transporter 2 (GLUT2) may be beneficial in controlling postprandial blood glucose levels. Gallic acid and ten of its derivatives were identified in the active fractions of Terminalia chebula Retz. fructus immaturus, a popular edible plant...

Ethnopharmacological relevance: With the mounting pandemic of glucose metabolism dysregulation and type 2 Diabetes Mellitus (T2DM), traditional medicine such as traditional Chinese medicine (TCM) recipes has been widely adopted as a part of therapeutic approach, especially in Asian countries. Aim of the study: A novel approach, which is adopted...

Two natural homogalacturonan (HG) pectins (MW ca. 20 kDa) were isolated from green tea based on their immunomodulatory activity. The crude tea polysaccharides (TPS1 and TPS2) were obtained from green tea leaves by hot water extraction and followed by 40% and 70% ethanol precipitation, respectively. Two homogenous water soluble polysaccharides (TPS1...

Two homogenous water-soluble polysaccharides (TPSR4-2B and TPSR4-2C) were obtained from pre-infused green tea. Their average molecular weights were estimated to be 41 kDa and 28 kDa, respectively. A combination of composition, methylation and configuration analysis, as well as NMR spectroscopy, indicated that both TPSR4-2B and TPSR4-2C were poly-(1...