Arctiin regulates collagen type 1α chain 1 mRNA expression in human dermal fibroblasts via the miR-378b-SIRT6 axis

Medicinal Plant Extracts Targeting UV-Induced Skin Damage: Molecular Mechanisms and Therapeutic Potential

The depletion of the ozone layer has intensified ultraviolet (UV) radiation exposure, leading to oxidative stress, DNA damage, inflammation, photoaging, and skin cancer. Medicinal plants, widely used in Traditional Herbal Medicine (THM), particularly in Traditional Chinese Medicine (TCM), have demonstrated significant therapeutic potential due to their well-characterized active compounds and established photoprotective effects. This review systematically evaluates 18 medicinal plants selected based on their traditional use in skin-related conditions and emerging evidence supporting their efficacy against UV-induced skin damage. Their bioactive components exert antioxidant, anti-inflammatory, DNA repair, and depigmentation effects by modulating key signaling pathways, including Nrf2/ARE-, MAPK/AP-1-, PI3K/Akt-, and MITF/TYR-related melanogenesis pathways. Moreover, novel drug delivery systems, such as exosomes, hydrogels, and nanoemulsions, have significantly enhanced the stability, bioavailability, and skin penetration of these compounds. However, challenges remain in standardizing plant-derived formulations, elucidating complex synergistic mechanisms, and translating preclinical findings into clinical applications. Future interdisciplinary research and technological advancements will be essential to harness the full therapeutic potential of medicinal plants for UV-induced skin damage prevention and treatment.

Role of non‑coding RNAs in UV‑induced radiation effects (Review)

Ultraviolet (UV) is divided into UVA (long-wave, 320-400 nm), UVB (middle-wave, 280-320 nm) and UVC (short-wave, 100-280 nm) based on wavelength. UV radiation (UVR) from sunlight (UVA + UVB) is a major cause of skin photodamage including skin inflammation, aging and pigmentation. Accidental exposure to UVC burns the skin and induces skin cancer. In addition to the skin, UV radiation can also impair visual function. Non-coding RNAs (ncRNAs) are a class of functional RNAs that do not have coding activity but can control cellular processes at the post-transcriptional level, including microRNA (miRNA), long non-coding RNA (lncRNA) and circulatory RNA (circRNA). Through a review of the literature, it was determined that UVR can affect the expression of various ncRNAs, and that this regulation may be wavelength specific. Functionally, ncRNAs participate in the regulation of photodamage through various pathways and play pathogenic or protective regulatory roles. In addition, ncRNAs that are upregulated or downregulated by UVR can serve as biomarkers for UV-induced diseases, aiding in diagnosis and prognosis assessment. Therapeutic strategies targeting ncRNAs, including the use of natural drugs and their extracts, have shown protective effects against UV-induced photodamage. In the present review, an extensive summarization of previous studies was performed and the role and mechanism of ncRNAs in UV-induced radiation effects was reviewed to aid in the diagnosis and treatment of UV-related diseases.

The role of sirtuins in dermal fibroblast function

The sirtuins are a family of seven proteins that perform a variety of dermatological functions and help maintain both the structure and function of the skin. More specifically, the sirtuins have been shown to be altered in multiple dermal cell types including dermal fibroblasts. The functions of dermal fibroblasts are extensive, and include playing a significant role in wound healing as well as helping to maintain the integrity of the skin. As dermal fibroblasts age, they can undergo a state of permanent cell cycle arrest, known as cellular senescence. This senescent process can occur as a result of various stressors, including oxidative stress, ultraviolet radiation -induced stress, and replicative stress. In recent years, there has been a growing interest in both enhancing the cutaneous fibroblast’s ability to facilitate wound healing and altering fibroblast cellular senescence. Thus, in this review, we examine the relationship between sirtuin signaling and dermal fibroblasts to understand how this family of proteins may modulate skin conditions ranging from the wound healing process to photocarcinogenesis associated with fibroblast senescence. Additionally, we offer supporting data from experiments examining the relationship between fibroblast senescence and sirtuin levels in an oxidative stress model indicating that senescent dermal fibroblasts exhibit diminished sirtuin levels. Furthermore, we survey the research on the role of sirtuins in specific dermatological disease states that where dermal fibroblast function has been implicated. Finally, we conclude with outlining potential clinical applications of sirtuins in dermatology. In sum, we find that the literature on the involvement of sirtuins in dermal fibroblasts is limited, with research still in its early stages. Nevertheless, intriguing preliminary findings merit additional investigation into the clinical implications of sirtuins in dermatology.

The Regulation of Collagen Processing by miRNAs in Disease and Possible Implications for Bone Turnover

This article describes several recent examples of miRNA governing the regulation of the gene expression involved in bone matrix construction. We present the impact of miRNA on the subsequent steps in the formation of collagen type I. Collagen type I is a main factor of mechanical bone stiffness because it constitutes 90-95% of the organic components of the bone. Therefore, the precise epigenetic regulation of collagen formation may have a significant influence on bone structure. We also describe miRNA involvement in the expression of genes, the protein products of which participate in collagen maturation in various tissues and cancer cells. We show how non-collagenous proteins in the extracellular matrix are epigenetically regulated by miRNA in bone and other tissues. We also delineate collagen mineralisation in bones by factors that depend on miRNA molecules. This review reveals the tissue variability of miRNA regulation at different levels of collagen maturation and mineralisation. The functionality of collagen mRNA regulation by miRNA, as proven in other tissues, has not yet been shown in osteoblasts. Several collagen-regulating miRNAs are co-expressed with collagen in bone. We suggest that collagen mRNA regulation by miRNA could also be potentially important in bone metabolism.

miR-378b Regulates Insulin Sensitivity by Targeting Insulin Receptor and p110α in Alcohol-Induced Hepatic Steatosis

Insulin resistance has been implicated in alcoholic liver disease. A previous study has shown that microRNAs (miRNAs) play a major role in the production, secretion, and function of insulin. MiRNAs are capable of repressing multiple target genes that in turn negatively regulate various physiological and pathological activities. However, current information on the biological function of miRNAs in insulin resistance is limited. The goal of the present study was to elucidate the role of miR-378b in alcohol-induced hepatic insulin resistance and its underlying mechanism. This study has observed that miR-378b is up-regulated in National Institute on Alcohol Abuse and Alcoholism (NIAAA) alcoholic mouse models as well as in ethanol-induced L-02 cells in vitro. Furthermore, miR-378b overexpression impaired the insulin signaling pathway, and inhibition of miR-378b improved insulin sensitivity in vivo and in vitro. A mechanistic study revealed that IR and p110α are direct targets of miR-378b. Together, these results suggest that miR-378b controls insulin sensitivity by targeting the insulin receptor (IR) as well as p110α and possibly play an inhibitory role in the development of insulin resistance, thereby providing insights into the development of novel diagnostic and treatment methods.

Long noncoding RNA HIF1A-AS2 facilitates cell survival and migration by sponging miR-33b-5p to modulate SIRT6 expression in osteosarcoma

Long noncoding RNAs (lncRNAs) are emerging as vital regulators in various physiological and pathological processes. It was recently found that lncRNA HIF1A-AS2 could play oncogenic roles in several cancers. However, the function and regulatory mechanism of lncRNA HIF1A-AS2 in osteosarcoma (OS) remain largely unclear. In this study, we demonstrated that HIF1A-AS2 was overexpressed in OS tissues and cells. Downregulation of HIF1A-AS2 significantly affects multiple biological functions in OS cells, including cell proliferation, cell cycle progression, cell apoptosis, cell migration, and cell invasiveness. Mechanistic investigations demonstrated that HIF1A-AS2 can interact with miR-33b-5p and negatively regulate its expression, thereby upregulating the protein expression of miR-33b-5p's target SIRT6. Additionally, in vivo experiments using a xenograft tumor mouse model revealed that downregulation of HIF1A-AS2 suppresses tumor growth in OS. Taken together, a newly identified regulatory mechanism for the lncRNA HIF1A-AS2-miR-33b-5p-SIRT6 axis was systematically studied in OS, which could be a promising target for the treatment of OS.