Narrow Results

As customizable biomaterials, hydrogels have attracted great promise in several industries, including drug delivery, tissue engineering, biosensing and regenerative medicine. Three-dimensional networks of these hydrophilic polymers exhibit special properties, such as increased water content, soft and flexible texture and biocompatibility, making them excellent candidates to simulate the extracellular matrix and promote cell development and tissue regeneration. In this review paper, we provide a comprehensive overview of hydrogels, focusing on the design concepts, synthesis processes and characterization techniques. Different types of hydrogel materials, including natural polymers, synthetic polymers and hybrid hydrogels, along with their unique properties and applications are discussed. Improvements in hydrogel-based platforms for controlled drug delivery are being investigated. Recent advances in bioprinting processes using hydrogels to create complex tissue constructs with excellent spatial control are also explored. Hydrogel performance is examined across multiple variables, including mechanical properties, degradation behavior and biological interactions, with an emphasis on the importance of tailoring hydrogel qualities for specific applications. This review paper also provides insights into future directions in hydrogel research, including stimuli-sensitive hydrogels, self-healing hydrogels and bioactive hydrogels, which promise promising advances in the field. In general, the aim of this review paper is to provide the reader with a detailed understanding of hydrogels and all of their potential applications, making them a valuable tool for scientists and researchers working on biomaterials and tissue engineering.

Fu-Ling is one of the most widely used Chinese herbal medicines. In this study, we investigated the regulatory effect of Fu-Ling on interleukin-10 (IL-10) production in vivo. Mice were i.p. administered 0.1 mg to 1.0 mg Fu-Ling per gram body weight daily for three days. The spleen cells were isolated and assayed for both IL-10 and immunoglobulin (Ig) production. Results indicated that the mice treated with Fu-Ling had significantly increased spleen cell ability to secrete IL-10. Spleen cells isolated from the mice injected with either 0.1 mg or 1.0 mg Fu-Ling per gram body weight also showed an increase in IL-10 mRNA expression. As IL-10 is a potent differentiation factor of B-lymphocytes, the possible effect of Fu-Ling on Ig production was also studied. Results indicated that Fu-Ling significantly induced an increase in IgG and IgA secretion by spleen cells but showed no effect on IgM secretion. Thus, Fu-Ling may affect the function of B-lymphocytes via stimulating IL-10 production.

Ginseng is one of the most widely used Chinese herbal medicines. In this report, the relatively short-term effect of ginseng extract on the immunoglobulin production and cytokine production was studied. The ginseng extract was prepared by boiling the ground ginseng root in 50% ethanol. The specific pathogen-free mice were intraperitoneally (i.p.) injected with various doses of ginseng extract for 3 consecutive days. The results indicated that the serum levels of immunoglobulin (Ig)M, IgG and IgA were significantly elevated after the mice were i.p. injected with 4 g/kg/day of ginseng extract. Under in vitro condition, the lipopolysaccharide (LPS)-stimulated spleen cells showed a dose-dependent increase in secretion of IgM, IgG and IgA. However, at a higher dosage (4 g/kg/day), the amount of IgA secretion began to decline. The serum level of interleukin (IL)-2, interferon (IFN)-γ [T-helper (Th)1-type cytokines] and IL-4 and IL-10 (Th2-type cytokines) were significantly elevated after the mice were i.p. injected with 2 g/kg/day or higher doses of ginseng extract. The amount of cytokine secretion by concanavalin A (Con A)-stimulated spleen cells was also significantly enhanced after the mice were i.p. injected with 0.4 g/kg/day or higher dose of ginseng extracted. To further confirm the results from enzyme-linked immunosorbent assay (ELISA), the spleen cells were cultured for 36 hours in the presence of 1 μg/ml of Con A. Total mRNA was isolated and assayed for mRNA expression using reverse transcriptase-polymerase chain reaction (RT-PCR). The results revealed that expression of IL-2 and IFN-γ mRNA were dose-dependently enhanced by the ethanol extract of ginseng. The levels of IL-4 and IL-10 mRNA expression were also elevated in the spleen cells of ginseng-treated mice in comparison with that of the control group. In addition, we observed that the concentrations of IgG1, IgG2a and IgG2b in culture supernatants of spleen cells were dose-dependently increased by in vivo treatment of ginseng extract, suggesting that both Th1- and Th2-type cytokines were involved in IgG production. Our observation in this study demonstrated that the Chinese herbal drug ginseng was able to regulate antibody production by augmenting Th1- (IL-2, IFN-γ) and Th2-type (IL-4, IL-10) cytokine production.