Construction of diallyltrisulfide nanoparticles for alleviation of ethanol-induced acute gastric injury.

Gastric ulcer, a significant health issue characterized by the degradation of the gastric mucosa, often arises from excessive gastric acid secretion and poses a challenge in current medical treatments due to the limited efficacy and side effects of first-line drugs. Addressing this, our study develops a novel therapeutic strategy leveraging gas therapy, specifically targeting the release of hydrogen sulfide (H2S) in the treatment of gastric ulcers. We successfully developed a composite nanoparticle, named BSA·SH-DATS, through a two-step process. Initially, bovine serum albumin (BSA) was sulfhydrated to generate BSA·SH nanoparticles via a mercaptosylation method. Subsequently, these nanoparticles were further functionalized by incorporating diallyltrisulfide (DATS) through a precise Michael addition reaction. This sequential modification resulted in the creation of BSA·SH-DATS nanoparticles. Our comprehensive in vitro and in vivo investigations demonstrate that these nanoparticles possess an exceptional ability for site-specific action on gastric mucosal cells under the controlled release of H2S in response to endogenous glutathione (GSH), markedly diminishing the production of pro-inflammatory cytokines, thereby alleviating inflammation and apoptosis. Moreover, the BSA·SH-DATS nanoparticles effectively regulate critical inflammatory proteins, including NF-κB and Caspase-3. Our study underscores their potential as a transformative approach for gastric ulcer treatment.

Angelica sinensis polysaccharides modified selenium nanoparticles for effective prevention of acute liver injury.

As a global public health issue, the treatment of acute liver injury (ALI) is severely limited due to the lack of specific drugs. In order to address the challenges, innovative strategies for selenium nanoparticles (Se NPs) with excellent antioxidant properties have been actively developed to effectively prevent ALI. However, the functional activity of Se NPs is severely affected by poor stability and bioavailability. The aim of this work is to develop a stabilization system (ASP-Se NPs) for Angelica sinensis polysaccharides modified Se NPs. The results showed that ASP-Se NPs with smaller size (62.38 ± 2.96 nm) showed good stability, specific accumulation in liver and enhanced cell uptake, thus exerting strong antioxidant and anti-inflammatory functions. The results of in vivo experiments further confirmed that ASP-Se NPs effectively prevented CCl4-induced ALI by improving liver function, inhibiting oxidative stress and inflammatory response, and liver pathological damage. This work provides a new alternative method for effectively preventing ALI and improving liver function.

Porphyra haitanensis polysaccharide-functionalized selenium nanoparticles for effective alleviation of ulcerative colitis.

Exacerbated intestinal inflammation, oxidative stress imbalance, and damage to intestinal mucosal barrier are closely related to the pathogenesis and progression of ulcerative colitis (UC). Selenium nanoparticles (Se NPs) have demonstrated promising potential to alleviate UC symptoms, however, their poor solubility and stability leading to aggregation and large precipitates have significantly limit their clinical application. In this study, we aimed to enhance the performance of Se NPs by functionalizing them with Porphyra haitanensis polysaccharide, yielding PHP-Se NPs. As expected, these PHP-Se NPs exhibited reduced particle size (70.51 ± 2.92 nm), enhanced cellular uptake compared to native Se NPs, and preferential accumulation in the colonic tissue, providing targeted UC treatment. In vivo animal experiments revealed that PHP-Se NPs significantly improved weight loss, shortened colon length, and higher disease activity index (DAI) scores in DSS-induced UC mice. Moreover, PHP-Se NPs significantly inhibited the levels of inflammatory factors in colitis tissues and oxidative stress in serum of UC mice, improved histological damage in colitis tissues, and restored the intestinal mucosal barrier. Taken together, our study offers an innovative approach to augment the bioavailability of Se NPs, presenting a promising strategy for the effective prevention and management of UC.

Mucoadhesive Hydrogel with Anti-gastric Acid and Sustained-Release Functions for Amelioration of DSS-Induced Ulcerative Colitis.

Mucoadhesive hydrogels with multifunctional properties such as gastric acid resistance and sustained drug release in the intestinal tract are highly desirable for the oral treatment of inflammatory bowel diseases (IBDs). Polyphenols are proven to have great efficacies compared with the first-line drugs for IBD treatments. We recently reported that gallic acid (GA) was capable of forming a hydrogel. However, this hydrogel is prone to easy degradation and poor adhesion in vivo. To tackle this problem, the current study introduced sodium alginate (SA) to form a gallic acid/sodium alginate hybrid hydrogel (GAS). As expected, the GAS hydrogel showed excellent antiacid, mucoadhesive, and sustained degradation properties in the intestinal tract. In vitro studies demonstrated that the GAS hydrogel significantly alleviated ulcerative colitis (UC) in mice. The colonic length of the GAS group (7.75 ± 0.38 cm) was significantly longer than that of the UC group (6.12 ± 0.25 cm). The disease activity index (DAI) value of the UC group was (5.5 ± 0.57), which was markedly higher than that of the GAS group (2.5 ± 0.65). The GAS hydrogel also could inhibit the expression of inflammatory cytokines, regulating macrophage polarization and improving the intestinal mucosal barrier functions. All these results indicated that the GAS hydrogel was an ideal candidate for oral treatment of UC.

Coassembly of Fiber Hydrogel with Antibacterial Activity for Wound Healing.

Wound healing remains a critical challenge due to its vulnerability to bacterial infection and the complicated inflammatory microenvironment. Herein, we report a novel antibacterial hydrogel constructed only by gallic acid (GA) and phycocyanin (PC), which is expected for the treatment of bacteria-infected wounds. These GA/PC hydrogels (GP) was found to coassemble into fibrous networks with a diameter of around 2 µm mainly through noncovalent interactions of hydrogen bonds, van der Waals force, and π interaction. Notably, these GP hydrogels showed excellent rheological properties (i.e., storage modulus of more than 9.0 × 104 Pa) and outstanding biocompatibility and antibacterial activities. Thanks to the incorporation of GA and PC, the GP hydrogels enabled adherence to the moist wound tissue and achieved a sustained release of GA and PC into the wound skin, therefore effectively attenuating inflammation and accelerating wound healing both in normal mice and bacteria-infected mice through regulating the expression of the tight junction protein and the alleviation of oxidative stress. Considering these results, these GP hydrogels are demonstrated to be a promising candidate for bacteria-infected wound healing.

Construction of an antibacterial hydrogel based on diammonium glycyrrhizinate and gallic acid for bacterial- infected wound healing.

The current antibacterial wound dressings with antibiotic substances or metal bactericidal agents may lead to severe multidrug resistance and poor biocompatibilities. Herein, we report an inherent antibacterial hydrogel constructed by only two naturally small molecules gallic acid (GA) and diammonium glycyrrhizinate (DG) for promoting Staphylococcus aureus (S. aureus)-infected wound healing. The resultant GAD hydrogel can be fabricated by co-assembly of these two materials through simple steps. Thanks to the incorporation of GA and DG, GAD hydrogel enabled a strong mechanical performance and great self-healing property with a sustained-release of drugs into skin wounds. Moreover, the cell viability assays showed that GAD hydrogel had good cytocompatibility by promoting cell proliferation and migration. In addition, GAD hydrogel had broad antibacterial efficiency against both Gram-positive and Gram-negative bacteria. Taken together, GAD hydrogel is a promising dressing to accelerate bacterial-infected wound healing through reconstructing an intact and thick epidermis without antibiotics or cytokines.

Construction of a sustained-release hydrogel using gallic acid and lysozyme with antimicrobial properties for wound treatment.

The purpose of this study is to provide a new strategy for constructing a temperature-controlled hydrogel as a promising agent for wound healing using natural products through physical co-assembly. Herein, the temperature-controlled physically assembled hydrogel consisting of gallic acid and lysozyme (GL) could be co-assembled into a regular fibrous structure accompanied by strong blue fluorescence with three-dimensional networks at micron levels through hydrophobic interactions, π-π interactions and hydrogen bonding. This GL hydrogel has excellent temperature sensitivity and self-healing properties, as proved by cycle high-low temperature tests. In addition, it possesses stable rheological properties, great sustained release ability, and could realize the spatiotemporal delivery of gallic acid and lysozyme. Biocompatibility and antibacterial tests proved that this well-assembled GL hydrogel has no cytotoxicity but excellent antibacterial activity. Both in vitro and in vivo experiments demonstrated that the GL hydrogel has excellent anti-inflammation efficiency and promotes the healing of chronic wounds by suppressing the expression of pro-inflammatory related genes. Tests using an E. coli-infected wound model confirmed that the GL hydrogel could terminate the inflammatory phase early and ultimately promote the healing of wounds infected by E. coli. This study provides a promising strategy for the effective treatment of wounds through a physical self-assembled hydrogel.

Resveratrol Triggered the Quick Self-Assembly of Gallic Acid into Therapeutic Hydrogels for Healing of Bacterially Infected Wounds.

Programing self-assembly of naturally bioactive molecules has been a wide topic of great significance for biomedical uses. Despite the fact that plant-derived polyphenols with catechol or pyrogallol moieties have been widely studied to construct nanocomplexes or nanocoatings via self-polymerization, there is no report on the self-assembly of these polyphenols into therapeutic hydrogels for potential applications. Here, we reported that adding a very small amount of resveratrol (Res) into the gallic acid (GA) aqueous solution could trigger the quick self-assembly of GA to form a fibrous hydrogel within 5 min through hydrogen bonds and π-π interactions. The length of GA/Res (GR) fibrils in gels varied from 100 to 1000 microns, with a diameter of around 1 µm. Notably, these GR hydrogels showed excellent colloid stability, providing better slow release and outstanding biocompatibility. Also, in vivo experiments indicated the hydrogels had high antibacterial effects and excellent wound healing capabilities in a total skin defect model via regulating the expression of inflammatory factors (IL-6, IL-1ß, and TNF-α) due to the release of therapeutic agents (GA and Res) into the matrix. Overall, our results provide a new strategy to accelerate self-assembly of GA by adding Res to form hydrogels, which is further proved as a promising therapeutic carrier for wound healing.

[Soil organic carbon storage in different aged Larix gmelinii plantations in Great Xing' an Mountains of Northeast China].

A sampling plot investigation was conducted to study the soil organic carbon (SOC) storage in 0-40 cm layer in 10-, 15-, 26- and 61 years old Larix gmelinii plantations in Great Xing' an Mountains of Northeast China as well as the temporal variation pattern of the SOC source/sink during the plantation management after the clear cutting of primary L. gmelinii forest. With the increasing age of the plantations, the SOC storage increased after an initial decrease, and the inflection point was at a stand age between 15- and 26-years old. Compared with that of primary forest, the SOC storage of the plantations played a role of carbon source at early stage (10-26 years old), but gradually transformed into carbon sink then, with a SOC storage of 158.91 t x hm(-2) in 61-year-old plantation. The SOC storage of the plantations increased with soil depth initially, but was higher in upper soil layer than in deeper soil layer after the stand age being 26, which implied that human disturbance had strong effects on the vertical distribution of SOC. It was considered that the appropriate cutting age for the L. gmelinii plantations in Great Xing' an Mountains could be at least 60 years old.

[Carbon storage, density, and distribution in forest ecosystems in Jilin Province of northeast China].

By using forest resources inventory data and field investigation data, this paper studied the carbon storage, density, and distribution characteristics in forest ecosystems in Jilin Province of Northeast China. The total carbon storage in the forest ecosystems was 1827.293 Tg C, and the carbon storages in arbor layer, shrub-grass layer, litter layer, and soil were 439.152 Tg C, 5.195 Tg C, 45.600 Tg C, and 1330.466 Tg C, accounting for 24.1%, 0.3%, 2.5%, and 73.1% of the total, respectively. The carbon density in the forest ecosystems was 225.304 Mg C x hm(-2), with 54.352 Mg C x hm(-2) in arbor layer, 0.643 Mg C x hm(-2) in shrub-grass layer, 5.644 Mg C x hm(-2) in litter layer, and 164.666 Mg C x hm(-2) in soil. Different types of the forest ecosystems had a carbon storage varied from 9.357 Tg C to 959.716 Tg C and a carbon density ranged from 180.648 Mg C * hm(-2) to 254.627 Mg C x hm(-2), with the highest values in soil and the lowest values in shrub-grass layer. Overall, the carbon storage and density in the forest ecosystems were greater in eastern mountainous area than in central and western plains. In the Province, middle-aged forests had a greater proportion than the forests in other age classes, and thereby, a proper management of the present forests could increase the carbon sequestration of the forest ecosystems.

[Vegetation carbon storage in Larix gmelinii plantations in Great Xing' an Mountains].

Through sampling site investigation, this paper studied the carbon storage of arbor, herb, and whole vegetation in 10-, 12-, 15-, 26-, and 61-year old Larix gmelinii plantations in Huzhong Forestry Bureau of Great Xing' an Mountains, Northeast China, and 'temporal for spatial' method was employed to approach the variations of the vegetation carbon storage during the growth of the plantations. The results revealed that the vegetation carbon storage in the plantations increased with stand age, and reached 105.69 t x hm(-2) at age of 61 years, representing a marked role as a carbon sink. The L. gmelinii plantations at the ages from 15 to 26 years had the strongest capability in carbon sequestration, in which, the carbon storage in trunk occupied 54.3% -73.9% of the total carbon storage of arbor, and, with the increase of stand age, the trunk's carbon storage to the total carbon storage of arbor as well as the trunk's carbon density increased. As for the other organs, the rate of their carbon storage to the total carbon storage of arbor decreased with stand age, while their carbon density increased first but eventually leveled off or had a slight decrease till at age of 61 years. Based on these results, the rotation age for the L. gmelinii plantations in Great Xing' an Mountains would properly be lengthened to at least 60 years.