Modulation of biomarkers related to tumor initiation and promotion in mouse skin by a natural β-glucuronidase inhibitor and its precursors.

Carcinogen-mediated labilization of lysosomal enzymes such as β-glucuronidase (βG) is often associated with the general process of inflammation. Therefore, the primary goal of this study was to demonstrate that exposing the skin of SENCAR mice to the natural βG inhibitor D-glucaro-1,4-lactone (1,4-GL) and its precursor D-glucuronic acid-γ-lactone (GUL), prior to and during 7,12-dimethylbenz[α]anthracene (DMBA) treatment inhibits not only epidermal hyperplasia but also inflammation in the mouse skin complete carcinogenesis model, i.e.

Dietary D-glucarate effects on the biomarkers of inflammation during early post-initiation stages of benzo[a]pyrene-induced lung tumorigenesis in A/J mice.

Previous studies showed that dietary calcium D-glucarate (CG) inhibited benzo[a]pyrene (B[a]P)-induced A/J mouse lung tumorigenesis, suppressing cell proliferation and chronic inflammation and inducing apoptosis during late post-initiation stages. The present study aimed to investigate changes in the homeostasis of cytokines in blood serum, as well as alterations in biomarkers of inflammation and apoptosis in lung tissue caused by dietary CG during early post-initiation stages of B[a]P-induced lung tumorigenesis. Two doses of 3 mg of B[a]P were given intragastrically to A/J mice 2 weeks apart.

Avicin D: a protein reactive plant isoprenoid dephosphorylates Stat 3 by regulating both kinase and phosphatase activities.

Avicins, a class of electrophilic triterpenoids with pro-apoptotic, anti-inflammatory and antioxidant properties, have been shown to induce redox-dependant post-translational modification of cysteine residues to regulate protein function. Based on (a) the cross-talk that occurs between redox and phosphorylation processes, and (b) the role of Stat3 in the process of apoptosis and carcinogenesis, we chose to study the effects of avicins on the processes of phosphorylation/dephosphorylation in Stat3. Avicins dephosphorylate Stat3 in a variety of human tumor cell lines, leading to a decrease in the transcriptional activity of Stat3.

[The biological role of D-glucaric acid and its derivatives: potential use in medicine].

D-glucaric acid is a natural non-toxic compound produced in small amounts by mammals, including humans. In mammals, D-glucaric acid and D-glucaro-l,4-lactone are end-products of the D-glucuronic acid pathway. The enzyme D-glucuronolactone dehydrogenase has been found to be responsible for the oxidation of the lactone of D-glucuronic acid to D-glucaro-l,4;6,3-dilactone.

Short-term biomarkers of cigarette smoke condensate tumor promoting potential in mouse skin.

Previous studies demonstrated that cigarette smoke condensates (CSCs) possessing significantly different tumorigenic potentials according to a standardized 30-week mouse skin tumor-promotion protocol could likewise be discriminated utilizing short-term indices of sustained hyperplasia and/or inflammation (G. M. Curtin et al.

Triterpenoid electrophiles (avicins) activate the innate stress response by redox regulation of a gene battery.

Avicins are proapoptotic and anti-inflammatory triterpene electrophiles isolated from an Australian desert tree, Acacia victoriae. The presence of two alpha,beta unsaturated carbonyl groups (Michael reaction sites) in the side chain of the avicin molecule prompted us to study its effects on NF-E2-related factor 2 (Nrf2), a redox-regulated transcription factor that controls the expression of a battery of detoxification and antioxidant proteins via its binding to antioxidant response element (ARE). Avicin D-treated Hep G2 cells showed translocation of Nrf2 into the nucleus and a time-dependent increase in ARE activity.