Hepatic endogenous defense potential of propolis after mercury intoxication

Mechanisms underlying the wound healing potential of propolis based on its in vitro antioxidant activity

BACKGROUND

Propolis is a resinous substance collected by honeybees, Apis mellifera, from various plant sources. Having various pharmacological and biological activities, it has been used in folk medicine and complementary therapies since ancient times.

PURPOSE

To evaluate the effects and underlying mechanism of the protective effects of the ethanol extract of Chinese propolis (EECP) on L929 cells injured by hydrogen peroxide (H₂O₂).

STUDY DESIGN

The wound healing activities of EECP in L929 cells with H₂O₂-induced damage were investigated.

METHODS

The main components of EECP were analyzed by RP-HPLC, and the free radical scavenging capacity and reducing power were also measured. The effects of EECP on the expression of antioxidant-related genes in fibroblast L929 cells were determined using qRT-PCR and western blotting.

RESULTS

EECP had significant protective effects against cell death induced by H₂O₂ and significantly inhibited the decline of collagen mRNA expression caused by H₂O₂ in L929 cells.

CONCLUSION

EECP induced the expression of antioxidant-related genes, such as HO-1, GCLM, and GCLC, which has great implications for the potential of propolis to alleviate oxidative stress in wound tissues. The protective effects of propolis have great implications for using propolis as a wound healing regent.

Preclinical antitoxic properties of Spirulina (Arthrospira)

CONTEXT

Spirulina (Arthrospira) exerts a wide spectrum of pharmacological activities which are mainly attributed to its antioxidant effect. However, Spirulina has also been reported (both in preclinical and in clinical scenarios) to exhibit other bioactive effects, including an antitoxic potential.

OBJECTIVE

We performed a systematic review of the literature, conducted in TOXNET, PubMed/MEDLINE, and Science Direct-Scopus; all available years were included. Searching criteria included the effects of Spirulina on experimental poisonings from arsenic, cadmium, carbon tetrachloride, deltamethrin, fluoride, hexachlorocyclohexane, iron, lead, lindane, and mercury.

RESULTS

In all cases, it was established that the blue-green alga, and its isolated compounds, effectively counteracted these pollutants toxic effects on the exposed organisms. Some molecular mechanisms are proposed, although they have not been fully elucidated yet.

CONCLUSION

Spirulina could be a useful coadjuvant agent within clinical practice for treatment of these or other pollutants poisonings.

The ameliorative effect of propolis against methoxychlor induced ovarian toxicity in rat

A study was designed to evaluate ameliorative effect of propolis against methoxychlor (MXC) induced ovarian toxicity in rat. The organochlorine pesticide (MXC) is a known endocrine disruptor with estrogenic, anti-estrogenic, and anti-androgenic properties. To investigate whether chronic exposure to MXC could cause ovarian dysfunction, two groups of Sprague-Dawley adult female rats were exposed to MXC alone in a dose of 200mg/kg, twice/weekly, orally or MXC dose as previous plus propolis in a dose of 200mg/l/day, in drinking water for 10 months. Another two groups of rat were given corn oil (control) or propolis. Multiple reproductive parameters, ovarian weight, serum hormone levels, ovarian oxidative status and ovarian morphology were examined. In MXC-exposed group, there is a significant decrease in body and ovarian weight vs. control. MXC decreases serum estradiol and progesterone levels. A significant increase in the levels of lipid peroxidation was obtained while a significant decrease of the total antioxidant was recorded. Ovarian histopathology showed primary, secondary and vesicular follicles displaying an atretic morphology. Increase in the ovarian surface epithelium height accompanied with vacuolated, pyknotic oocytes were obtained. The previous toxic effects were neutralized by the administration of propolis in MXC+propolis group. The present results suggest that propolis may be effective in decreasing of MXC-induced ovarian toxicity in rat.

N-acetyl cysteine and selenium protects mercuric chloride-induced oxidative stress and antioxidant defense system in liver and kidney of rats: a histopathological approach

Mercury exposure is second-most common cause of metal poisoning which is quite stable and biotransformed to highly toxic metabolites thus eliciting biochemical alterations and oxidative stress. The aim of present study describes the protective effect of selenium either alone or in combination with N-acetyl cysteine (NAC) against acute mercuric chloride poisoning. The experiment was carried out in male albino Sprague Dawley rats (n=30) which was divided into five groups. Group 1 served as control. Groups 2-5 were administered mercuric chloride (HgCl2: 12mol/kg, i.p.) once only, group 2 served as experimental control. Animals of groups 3, 4 and 5 were received N-acetyl cysteine (NAC: 0.6mg/kg, i.p.) and selenium (Se: 0.5mg/kg, p.o.) and NAC with Se in combination. Acute HgCl2 toxicity caused significant rise in serum alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, lactate dehydrogenase, albumin, bilirubin, γ-glutamyl transpeptidase, cholesterol, triglycerides, protein, urea, creatinine, uric acid and blood urea nitrogen content. Animals also showed significantly higher mercury content in liver and kidney, significant rise in lipid peroxidation level with concomitant decrease in reduced glutathione content and the antioxidant enzyme activities of superoxide dismutase and catalase after HgCl2 exposure. Results of the present investigation clearly showed that combination therapy with NAC+Se provide maximum protection against mercury toxicity than monotherapy (alone treated groups) by preventing oxidative degradation of biological membrane from metal mediated free radical attacks.