Bifidobacterium longum 68S mediated gut-skin axis homeostasis improved skin barrier damage in aging mice

Molecular mechanism of melatonin-mediated mitophagy regulating proline production to ameliorate skin aging

Collagen loss is one of the major contributor to signs of skin aging such as dryness, roughness, and wrinkle formation, which is closely linked to a decline in the amount of proline produced in mitochondria. Melatonin has been shown to improve several clinical signs of skin aging, while the mechanism is unclear. In our study, we found that mitophagy, proline synthesis key enzyme NADK2 and proline and collagen levels were significantly reduced, while oxidative stress levels increased in aging skin, and melatonin supplementation could effectively up-regulate mitophagy level and restore proline synthesis and further improved skin aging. However, proline supplementation could also exert an anti-aging effect, while it had no effect on the mitochondrial dysfunction. Moreover, our study indicated that melatonin enters the cell by binding to the MT1 receptor and then enters the mitochondria via the PEPT1 transporter to exert its mitochondrial protective effects. This study helps to elucidate the mechanism of mitochondrial dysfunction-induced skin aging, and provides new theoretical guidance for revealing the mechanism of skin aging and rationally utilizing endocrine hormones to improve skin aging, which has a broad application prospect.

Non-Animal Hyaluronic Acid and Probiotics Enhance Skin Health via the Gut-Skin Axis: An In Vitro Study on Bioavailability and Cellular Impact

Hyaluronic acid (HA) represents a pivotal component of the extracellular matrix, particularly within the context of the skin. The absorption and metabolism of orally ingested HA have been extensively investigated due to the prevalence of HA-based supplements. The objective of this study was to evaluate the impact of a combination of non-animal HA and Bifidobacterium longum novaBLG1 on dermal health following intestinal transit. The bioavailability of the compound was evaluated using a model that reproduced the human intestinal barrier in vitro, and its biological effects were investigated on skin cells via the gut-skin axis. The results demonstrated that probiotics augmented the absorption of non-animal HA by approximately 30% in comparison to non-animal HA alone and by 82% in comparison to sodium hyaluronate. Furthermore, the combination demonstrated a notable enhancement in skin cell proliferation, with increases of 16%, 8%, and 29.7% over 144 h in comparison to non-animal hyaluronan, Bifidobacterium longum novaBLG1, and sodium hyaluronate, respectively. The combination was observed to positively affect all markers of skin health and well-being, achieving its goals without any adverse effects on the gut. This approach offers a novel method for enhancing skin health.

The vital role of melatonin in the intestinal mucosal barrier integrity in chick

BACKGROUND

The intestinal tract, as the main place for nutrient digestion and absorption, is closely related to the health of livestock and poultry. Melatonin secreted by the pineal gland acts as an endocrine transport signaling molecule to regulate intestinal function. However, the effect on intestinal function after pineal removal is unclear.

METHODS

We raised 24 chicks under 400-700 nm white light with or without pinealectomy for 21 days. We used electron microscopy, HE staining, PAS staining, immunohistochemistry, immunofluorescence staining and western blot to detect intestinal physical and to explore the effect of melatonin secreted by the pineal gland on the intestinal mucosa barrier function.

RESULTS

The results showed that after pineal gland removal, the structure of the intestinal villi is severely damaged. Moreover, there was an obviously down-regulation in the villi length, the number of goblet cells and and its secretion of MUC2 protein, the expression level of tight junction proteins (Occludin and ZO-1) and lysozyme secreted by paneth cells, number of PCNA positive cells and macrophage, and an up-regualtion in crypt depth and apoptosis level after pinealectomy, suggesting pinealectomy-mediated melatonin level decrease damaged the intestinal physical, chemical and immune barriers.

CONCLUSION

Our findings provide new theoretical support for the future use of melatonin in intestinal development and new ideas about the relationship between endocrine hormone and intestinal physiology.

Isolation, structure, biological activity and application progress of ginseng polysaccharides from the Araliaceae family

Phytopolysaccharides are a class of natural macromolecules with a range of biological activities. Ginseng, red ginseng, American ginseng, and Panax notoginseng are all members of the Araliaceae family. They are known to contain a variety of medicinal properties and are typically rich in a wide range of medicinal values. Polysaccharides represent is one of the principal active ingredients in the aforementioned plants. However, there is a paucity of detailed reports on the separation methods, structural characteristics and comparison of various pharmacological effects of these polysaccharides. This paper presents a review of the latest research reports on ginseng, red ginseng, American ginseng and ginseng polysaccharides. The differences in extraction, separation, purification, structural characterization, and pharmacological activities of the four polysaccharides are compared and clarified. Upon examination of the current research literature, it becomes evident that the extraction and separation processes of the four polysaccharides are highly similar. Modern pharmacological studies have corroborated the multiple biological activities of these polysaccharides. These activities encompass a range of beneficial effects, including antioxidant stress injury, fatigue reduction, tumor inhibition, depression alleviation, regulation of intestinal flora, immunomodulation, diabetes management, central nervous system protection, anti-aging, and improvement of skin health. This paper presents a review of studies on the extraction, purification, characterization, and bioactivities of four natural plant ginseng polysaccharides. Furthermore, the review presents the most recent research findings on their pharmacological activities. The information provides a theoretical basis for the future application of natural plant polysaccharides and offers a new perspective for the in-depth development of the medicinal value of ginseng in the clinical practice of traditional Chinese medicine.

Dual intervention on the gut and skin microbiota attenuates facial cutaneous aging

The gut and skin microbiota are microbial barriers, resisting harmful foreign microorganisms and maintaining internal homeostasis. Dysbiosis of the gut and skin microbiota is involved in aging progression. However, interventions targeting facial skin wellness taking into account the gut-skin axis are scarce. In this study, the impact of an eight-week intervention with oral (O), topical (T), and both oral and topical (OT) xylo-oligosaccharides (XOS) by regulating gut and skin microbiota on facial cutaneous aging was investigated in a double-blind placebo-controlled trial in females. An increase in the proportion of participants with skin rejuvenation was observed, along with a significant reduction in facial pores after OT intervention. The reduction of cutaneous Cutibacterium by OT intervention was greater than that in the O and T groups. These interventions can change the skin microbial structure. Intestinal Bifidobacterium was enriched only by dual treatment with oral and topical XOS. Function prediction analysis revealed a decrease in K02770 encoding fructose-1-phosphate kinase involved in de novo lipid synthesis from fructose with dual intervention, suggesting that inhibition of lipophilic Cutibacterium may contribute to reducing facial pores. Overall, the dual XOS intervention approach is most effective for improving both gut and skin microbiota, as well as facial skin aging.

Genetic insights into the gut microbiota and risk of facial skin aging: A Mendelian randomization study

BACKGROUND

A growing number of experimental studies have shown an association between the gut microbiota (GM) and facial skin aging. However, the causal relationship between GM and facial skin aging remains unclear to date.

METHODS

We conducted a two-sample Mendelian randomization (MR) analysis to investigate the potential causal relationship between GM and facial skin aging. MR analysis was mainly performed using the inverse-variance weighting (IVW) method, complemented by the weighted median (MW) method, MR-Egger regression, and weighted mode, and sensitivity analysis was used to test the reliability of MR analysis results.

RESULTS

Eleven GM taxa associated with facial skin aging were identified by IVW method analysis, Family Victivallaceae (p = 0.010), Genus Eubacterium coprostanoligenes group (p = 0.038), and Genus Parasutterella (p = 0.011) were negatively associated with facial skin aging, while Phylum Verrucomicrobia (p = 0.034), Family Lactobacillaceae (p = 0.017) and its subgroups Genus Lactobacillus (p = 0.038), Genus Parabacteroides (p = 0.040), Genus Eggerthella (p = 0.049), Genus Family XIII UCG001 (p = 0.036), Genus Phascolarctobacterium (p = 0.027), and Genus Ruminococcaceae UCG005 (p = 0.012) were positively associated with facial skin aging. At Class and Order levels, we did not find a causal relationship between GM and facial skin aging. Results of sensitivity analyses did not show evidence of pleiotropy and heterogeneity.

CONCLUSION

Our findings confirm the causal relationship between GM and facial skin aging, providing a new perspective on delaying facial aging.

Dietary Isoeugenol Supplementation Attenuates Chronic UVB-Induced Skin Photoaging and Modulates Gut Microbiota in Mice

Photoaging, the primary cause of skin aging damage, results from chronic ultraviolet (UV) exposure, leading to dryness and wrinkle formation. Nutritional intervention has emerged as a practical approach for preventing and addressing the effect of skin photoaging. The primary aromatic compound isolated from clove oil, isoeugenol (IE), has antibacterial, anti-inflammatory, and antioxidant qualities that work to effectively restrict skin cancer cell proliferation. This investigation delved into the advantages of IE in alleviating skin photoaging using UVB-irradiated skin fibroblasts and female SKH-1 hairless mouse models. IE alleviated UVB-induced photodamage in Hs68 dermal fibroblasts by inhibiting matrix metalloproteinase secretion and promoting extracellular matrix synthesis. In photoaged mice, dietary IE reduced wrinkles, relieved skin dryness, inhibited epidermal thickening, and prevented collagen loss. Additionally, the intestinal dysbiosis caused by prolonged UVB exposure was reduced with an IE intervention. The results of Spearman's analysis showed a strong correlation between skin photoaging and gut microbiota. Given the almost unavoidable UVB exposure in contemporary living, this research demonstrated the efficacy of dietary IE in reversing skin photoaging, presenting a promising approach to tackle concerns related to extrinsic skin aging.