Effect of gamma irradiated hyaluronic acid on acetaminophen induced acute hepatotoxicity

Dandelion polyphenols protect against acetaminophen-induced hepatotoxicity in mice via activation of the Nrf-2/HO-1 pathway and inhibition of the JNK signaling pathway

We investigated the liver protective activity of dandelion polyphenols (DP) against acetaminophen (APAP; Paracetamol)-induced hepatotoxicity. Mice were acclimated for 1 week and randomly divided into the following groups (n = 9 per group): Control, APAP, APAP + DP (100 mg·kg^-1), APAP + DP (200 mg·kg^-1), and APAP + DP (400 mg·kg^-1) groups. Mice were pretreated with DP (100, 200, and 400 mg·kg^-1) by oral gavage for 7 d before being treated with 350 mg·kg^-1 APAP for 24 h to induced hepatotoxicity. Severe liver injury was observed, and hepatotoxicity was analyzed after 24 h by evaluation of biochemical markers, protein expressions levels, and liver histopathology. Pretreatment with DP was able to restore serum liver characteristics (aspartate transaminase, AST; alanine aminotransferase, ALT; alkaline phosphatase, AKP), improve redox imbalance (superoxide dismutase, SOD; glutathione, GSH; malondialdehyde, MDA), and decrease inflammatory factors (tumor necrosis factor-α, TNF-α; interleukin-1β, IL-1β). Pretreatment with DP also significantly inhibited the expression levels of nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). Furthermore, DP pretreatment could inhibit the apoptosis of liver cells caused by APAP through up-regulation of Bcl-2 and down-regulation of Bax and caspase-9 protein. DP also down-regulated p-JNK protein expression levels to inhibit APAP-induced mitochondrial oxidative stress and up-regulated the expression of Nrf-2 and its target gene HO-1. The histopathological staining demonstrated that DP pretreatment could inhibit APAP-induced hepatocyte infiltration, congestion, and necrosis. Our results demonstrate that DP pretreatment could protect against APAP-induced hepatic injury by activating the Nrf-2/HO-1 pathway and inhibition of the intrinsic apoptosis pathway.

Fabrication and characterization of cobalt hyaluronic acid nanostructure via gamma irradiation for improving biomedical applications

Aqueous dispersed cobalt hyaluronic acid nanostructure (CoHANs) was synthesized using cobalt ion (Co⁺²) as precursor and natural polysaccharide hyaluronic acid (HA) as stabilizing agent and gamma irradiation as reducing agent. The synthesized CoHANs are characterized by UV-Vis. spectroscopy, Dynamic light scattering (DLS), X-ray diffraction (XRD) and Fourier Transform Infrared spectroscopy (FT-IR). The morphology and surface appearance of CoHANs has been observed by SEM images. The particles size and shape of CoHANs were estimated by TEM images and was found to be 12.0 nm. XRD analysis of the CoHANs confirmed the formation of crystalline nanoparticles. The nucleation and growth mechanism of CoHANs was also discussed. The size of nanoparticles was found to be influenced by certain parameters such as the choice of stabilizer and cobalt ion concentration and the absorbed dose. The results indicated the CoHANs possesses high activity than cobalt ion and HA. The present study explored the positive role of CoHANs as an antitumor agent on different cell carcinoma in vitro. Excellent bactericidal spatially against pathogenic bacteria and fungicidal activity was shown by the CoHANs.

Gamma-Irradiation-Prepared Low Molecular Weight Hyaluronic Acid Promotes Skin Wound Healing

In this study, we prepared low-molecular-weight hyaluronic acid (LMWHA) powder by γ-irradiation. The chemical and physical properties of γ-irradiated LMWHA and the in vitro cellular growth experiments with γ-irradiated LMWHA were analyzed. Then, hyaluronic acid exposed to 20 kGy of γ-irradiation was used to fabricate a carboxymethyl cellulose (CMC)/LMWHA fabric for wound dressing. Our results showed that γ-irradiated LMWHA demonstrated a significant alteration in carbon-oxygen double bonding and can be detected using nuclear magnetic resonance and ultraviolet (UV)-visible (Vis) spectra. The γ-irradiated LMWHA exhibited strain rate-dependent Newton/non-Newton fluid biphasic viscosity. The viability of L929 skin fibroblasts improved upon co-culture with γ-irradiated LMWHA. In the in vivo animal experiments, skin wounds covered with dressings prepared by γ-irradiation revealed acceleration of wound healing after two days of healing. The results suggest that γ-irradiated LMWHA could be a potential source for the promotion of skin wound healing.

Hepatoprotective effects of kombucha tea: identification of functional strains and quantification of functional components

BACKGROUND

Kombucha tea (KT), a traditional health beverage containing potential hepatoprotective agents, is fermented from sugared tea by a symbiotic culture of yeast and bacteria for 8 days. However, the functional strains that produce components for the hepatoprotective property of KT remain unclear. Multiple strains are involved in traditional KT production. Therefore, KT has not been standardized or produced commercially. This study aimed to identify the functional strains and quantify the functional components with hepatoprotective effects in kombucha tea.

RESULTS

Gluconacetobacter sp. A4 was one of the microorganisms in KT in which the D-saccharic acid-1,4-lactone (DSL) produced by G. sp. A4 was significantly higher than that produced by original tea fungus at 8 days of fermentation. Traditional KT (TKT, tea broth fermented by mixed tea fungus), modified KT (MKT, fermented by single G. sp. A4), and DSL significantly inhibited the acetaminophen-induced increase of alanine aminotransferase, alkaline phosphatase, triglyceride and malondialdehyde, as well as facilitating the reduction of total antioxidant capacity in mice. Furthermore, MKT and TKT are both similar to DSL in terms of protection against acetaminophen-induced liver injury in mice. These results suggested a positive relationship between DSL content and the hepatoprotective effect of TKT, MKT and DSL groups.

CONCLUSION

G. sp. A4 was concluded to be a potential functional strain and DSL might be the key functional component for the hepatoprotective property in KT. The stronger capability of G. sp. A4 in producing DSL makes it a better choice for the commercial production of KT.

Effect of hesperidin pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen-induced acute liver injury

AIM: To investigate the protective effect of hesperidin (HDN) pretreatment on the expression of apoptosis-related genes in the liver of mice with acetaminophen (APAP)-induced acute liver injury.

METHODS: Sixty male Balb/c mice were randomly divided into six groups, including normal group, model group, bifendate group, low-, medium-, and high-dose HDN groups. The HDN groups were intragastrically given different doses of hesperidin for 10 d. The bifendate group was given bifendate. Acute liver injury was induced by injecting APAP in all mice except those in the normal group. After 16 h, all mice were sacrificed. Liver index was calculated. Serum levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured. The activity of superoxide dismutase (SOD) and the contents of glutathione peroxidase (GSH-PX) and malondialdehyde (MDA) in liver homogenates were determined. Pathological changes in hepatic tissue were observed under an optical microscope. Apoptosis of hepatic cells was detected by TUNEL assay. The expression of Bcl-2 and Bax mRNAs in hepatic tissue was measured by reverse transcription polymerase chain reaction (RT-PCR).

RESULTS: Compared to the normal group, liver index, serum levels of ALT and AST, and the contents of MDA were significantly increased, and the activity of SOD and contents of GSH-PX in liver homogenates were significantly decreased in the model group (5.41% ± 0.68% vs 4.38% ± 0.17%, 1456.49 U/L ± 413.45 U/L vs 45.36 U/L ± 11.98 U/L, 1929.34 U/L ± 810.19 U/L vs 78.49 U/L ± 10.22 U/L, 32.04 nmol/mgprot ± 9.32 nmol/mgprot vs 11.83 nmol/mgprot ± 1.72 nmol/mgprot, 119.29 U/mgprot ± 33.02 U/mgprot vs 327.22 U/mgprot ± 26.66 U/mgprot, 75.89 μmol/L ± 20.21 μmol/Lvs 122.73 μmol/L ± 6.70 μmol/L, all P < 0.01). However, liver index, serum levels of ALT and AST, and the contents of MDA were significantly lower, and the activity of SOD and contents of GSH-PX were significantly higher in the bifendate group, high- and medium-dose HDN groups than in the model group (4.65% ± 0.61%, 4.59% ± 0.57%, 4.73% ± 0.63%vs 4.38% ± 0.17%; 66.36 U/L ± 13.43 U/L, 225.29 U/L ± 53.02 U/L, 773.06 U/L ± 251.27 U/L vs 1456.49 U/L ± 413.45 U/L; 105.75 U/L ± 17.02 U/L, 540.92 U/L ± 170.57 U/L, 906.78 U/L ± 226.38 U/L vs 1929.34 U/L ± 810.1 U/L; 15.74 nmol/mgprot ± 2.98 nmol/mgprot, 16.04 nmol/mgprot ± 4.92 nmol/mgprot, 20.85 nmol/mgprot ± 6.04 nmol/mgprot vs 32.04 nmol/mgprot ± 9.32 nmol/mgprot; 222.52 U/mgprot ± 56.11 U/mgprot, 245.95 U/mgprot ± 41.90 U/mgprot, 198.12 U/mgprot ± 68.09 U/mgprot vs 119.29 U/mgprot ± 33.02 U/mgprot; 108.70 μmol/L ± 25.96 μmol/L, 107.39 μmol/L ± 32.60 μmol/L, 98.90 μmol/L ± 10.71 μmol/L vs 75.89 μmol/L ± 20.21 μmol/L, all P < 0.01 or 0.05). The spleen index showed no significant differences among each group (all P > 0.05). Massive patchy necrosis surrounding the central vein, cellular swelling, massive inflammatory cell infiltration, and significant liver cell apoptosis were observed in liver tissues of mice in the model group; however, these pathological changes and cell apoptosis were significantly alleviated in the bifendate group and HDN groups. Such improvement was most obvious in the bifendate group and high-dose HDN group. APAP could significantly up-regulate Bax mRNA expression, down-regulate Bcl-2 mRNA expression, and decrease the Bcl-2/Bax ratio (0.68 ± 0.03 vs 0.28 ± 0.02, 0.21 ± 0.04 vs 0.58 ± 0.01; both P < 0.01). However, Bcl-2 mRNA expression was significantly up-regulated, Bax mRNA expression was significantly down-regulated and the Bcl-2/Bax ratio was significantly increased in the bifendate group, high- and medium-dose HDN groups (0.22 ± 0.04, 0.56 ± 0.01, 0.75 ± 0.01 vs 0.21 ± 0.04; 0.67 ± 0.06, 0.26 ± 0.005, 0.28 ± 0.02 vs 0.68 ± 0.03, all P < 0.05).

CONCLUSION: HDN pretreatment protects mice from acetaminophen-induced liver injury possibly via mechanisms associated with inhibiting lipid peroxidation and regulating the expressions of apoptosis-related genes.