Propolis protects against 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced toxicity in rat hepatocytes

Antioxidant activity and protective effect of propolis against carbon tetrachloride-induced liver and kidney injury by modulation of oxidative parameters

Background and Aim:

Propolis has a protective effect against cellular damage caused by toxic agents such as drugs, metals, xenobiotics, and chemicals. The aim of this study was to investigate the antioxidant activity and the effect of ethanolic extract of propolis on carbon tetrachloride (CCl4)-induced oxidative stress on kidney and liver injury in rat.

Materials and Methods:

The study quantified phenol, flavone, and flavonol in propolis and assessed antioxidant activity using 2, 2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power, and molybdate. The investigators used four groups of rats to study the effect of propolis on CCl₄-induced toxicity. Propolis extract was given orally (500 mg/kg) for 12 days, and CCl_{4 (}1 mL/kg) was administered intraperitoneally on day 5 of the experiment. Blood and tissue samples of the liver and kidney were collected on day 13 to measure biochemical and oxidative parameters. The parameters included malondialdehyde (MDA), protein carbonyl formation (PCO), advanced oxidation protein products (AOPP), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), and ascorbic acid (AA). Biochemical parameters included liver enzymes, blood urea (BU), creatinine, and uric acid (UA).

Results:

CCl₄ decreased antioxidant agents, including CAT, GPx, GSH, and AA in the liver and kidney tissues. The oxidative agents’ levels, including MDA, PCO, and AOPP, increased by CCl₄ compared to the control group. CCl₄ increased liver enzymes, UA, BU, and creatinine in the blood samples. Propolis significantly alleviated liver and kidney function, improved antioxidant parameters, and decreased levels of oxidative agents.

Conclusion:

The data showed for the 1^st time that Moroccan propolis has a protective effect against CCl₄-induced kidney and liver toxicity by maintaining the activity of the antioxidant defense system, which was most likely due to its antioxidant activity.

In vitro transcriptome response to propolis in differentiated SH-SY5Y neurons

Propolis is the extract of a resinous compound that protects plants from both cold and microorganism attack and has gained a strong and sticky property because it is transformed after being collected by honey bees. Up to date, many studies have shown that propolis exhibited various beneficial biological activities, such as antifungal, antibacterial, antiviral, antioxidant, antimutagenic, and antitumor effects. Recent reports propounded the in vitro and in vivo neuroprotective effect of propolis; however, the exact molecular genetic mechanisms are still unclear. Therefore, we aimed to investigate the toxicogenomic and beneficial properties, including cytotoxic, antioxidant, apoptotic/necrotic as well as genotoxic effects of propolis (1.56-200 µg/ml) on differentiated SH-SY5Y neuronal cells. Additionally, microarray analysis was conducted on cell cultures following propolis application to explore gene differentiation. Differentially expressed genes were further analyzed using string software to characterize protein-protein interactions between gene pathways. Our results revealed that propolis applications could not have a prominent effect on cell viability even at concentrations up to 200 µg/ml. The highest propolis concentration induced apoptotic rather than necrotic cell death. The alterations in gene expression profiles, including CYP26A1, DHRS2, DHRS3, DYNC1I1, IGF2, ITGA4, SVIL, TGFβ1, and TGM2 could participate in the neuroprotective effects of propolis. In conclusion, propolis supplementation exerted remarkable advantageous; thus, it may offer great potential as a natural component in the prevention and treatment of neurodegenerative disorders. Whole-genome gene expression pattern following propolis application was investigated for the first time in neuronal cell culture to fill a gap in the literature about propolis toxicogenomics. PRACTICAL APPLICATIONS: Propolis is a very rich product in terms of benefits. In addition to its antibacterial, antiviral, antifungal, and anti-inflammatory content, it is known to have preventive and therapeutic properties for many different ailments. On the other hand, molecular mechanisms of propolis on gene expression differentiations haven't been investigated until now. Moreover, gene expression pattern is vital for all living organisms to maintain homeostasis. Thus, we conduct an experiment series for analyzing gene expression differentiation effects on neuronal cells to understand beneficial properties of propolis. Hence, it could be possible to comment on the use of propolis as a nutritional factor and beneficial diet.

Evidence of Some Natural Products with Antigenotoxic Effects. Part 2: Plants, Vegetables, and Natural Resin

Cancer is one of the leading causes of death worldwide. The agents capable of causing damage to genetic material are known as genotoxins and, according to their mode of action, are classified into mutagens, carcinogens, or teratogens. Genotoxins are also involved in the pathogenesis of several chronic degenerative diseases, including hepatic, neurodegenerative, and cardiovascular disorders; diabetes; arthritis; cancer; chronic inflammation; and ageing. In recent decades, researchers have found novel bioactive phytocompounds able to counteract the effects of physical and chemical mutagens. Several studies have shown the antigenotoxic potential of different fruits and plants (Part 1). In this review (Part 2), we present a research overview conducted on some plants and vegetables (spirulina, broccoli, chamomile, cocoa, ginger, laurel, marigold, roselle, and rosemary), which are frequently consumed by humans. In addition, an analysis of some phytochemicals extracted from those vegetables and the analysis of a resin (propolis),whose antigenotoxic power has been demonstrated in various tests, including the Ames assay, sister chromatid exchange, chromosomal aberrations, micronucleus, and comet assay, was also performed.

Protective Effect of Propolis in Proteinuria, Crystaluria, Nephrotoxicity and Hepatotoxicity Induced by Ethylene Glycol Ingestion

BACKGROUND AND AIMS

Propolis is a natural honeybee product with wide biological activities and potential therapeutic properties. The aim of the study is to evaluate the protective effect of propolis extract on nephrotoxicity and hepatotoxicity induced by ethylene glycol in rats.

METHODS

Five groups of rats were used. Group 1 received drinking water, group 2 received 0.75% ethylene-glycol in drinking water, group 3 received 0.75% ethylene-glycol in drinking water along with cystone 500 mg/kg/body weight (bw) daily, group 4 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 100 mg/kg/bw daily, and group 5 received 0.75% ethylene-glycol in drinking water along with propolis extract at a dose of 250 mg/kg/bw daily. The treatment continued for a total of 30 d. Urinalyses for pH, crystals, protein, creatinine, uric acid and electrolytes, and renal and liver function tests were performed.

RESULTS

Ethylene-glycol increased urinary pH, urinary volume, and urinary calcium, phosphorus, uric acid and protein excretion. It decreased creatinine clearance and magnesium and caused crystaluria. Treatment with propolis extract or cystone normalized the level of magnesium, creatinine, sodium, potassium and chloride. Propolis is more potent than cystone. Propolis extract alleviates urinary protein excretion and ameliorates the deterioration of liver and kidney function caused by ethylene glycol.

CONCLUSIONS

Propolis extract has a potential protective effect against ethylene glycol induced hepatotoxicity and nephrotoxicity and has a potential to treat and prevent urinary calculus, crystaluria and proteinuria.

Mitigating effect of Indian propolis against mitomycin C induced bone marrow toxicity

A major drawback with cancer chemotherapy is its severe toxic effects on non-target tissues. Assessment of natural products for their protective effect against anticancer drugs-induced toxicity is gaining importance in cancer biology. The present study was aimed at assessing the protective effect of hydroethanolic extract of Indian propolis (HEIP) against mitomycin C (MMC)-induced genotoxicity and cytotoxicity. Swiss albino mice were injected with various doses of HEIP (100, 200, 300, 400, 600 and 800 mg/kg b. wt., i.p) 1 h prior to MMC (8 mg/kg, i.p.) injection. The geno- and cyto-toxicities were evaluated in mice by performing bone marrow micronucleus and TUNEL assays. In vitro antioxidant and lipid peroxidation inhibitory assays were carried out to understand the mechanism of the protective effects. The significant increase in the frequency of micronculeated cells (12.51 ± 0.48), apoptotic cells (23.43 ± 1.86) and reduction in P/N ratio (0.69 ± 0.04) compared with control indicated the potential geno- and cytotoxic effects of MMC in bone marrow. Pretreatment with HEIP resulted in the significant recovery of the toxic effects induced by MMC. HEIP at 400 mg/kg b. wt. was found to be the optimum dose imparting the maximum protective effects. The in vitro antioxidant and lipid peroxidation inhibitory assays suggest that the extract possesses substantial free radical scavenging activities. In conclusion, HEIP possesses substantial geno- and cyto-protective properties against MMC, which could be mediated through efficient free radical scavenging and inhibitory effect on lipid peroxidation.

Ameliorative effects of docosahexaenoic acid on the toxicity induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin in cultured rat hepatocytes

The 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is an environmental contaminant toxicant that mediates carcinogenic effects associated with oxidative DNA damage. Docosahexaenoic acid (DHA) with antioxidant functions has many biochemical, cellular, and physiological functions for cells. The present study assessed, for the first time, the ameliorative effect of DHA in alleviating the toxicity of TCDD on primary cultured rat hepatocytes (HEPs). In vitro, isolated HEPs were incubated with TCDD (5 and 10 μM) in the presence and absence of DHA (5, 10, and 20 μM) for 48 h. The cell viability was detected by 3-(4,5-dimethylthiazol-2-yl) 2,5-diphenyltetrazolium bromide (MTT) assay and lactate dehydrogenase (LDH) release. DNA damage was analyzed by liver micronucleus assay and 8-oxo-2-deoxyguanosine (8-OH-dG) level. In addition, total antioxidant capacity (TAC) and total oxidative stress (TOS) were assessed to determine the oxidative injury in HEPs. The results of MTT and LDH assays showed that TCDD decreased cell viability but not DHA. On the basis of increasing treatment concentrations, the dioxin caused significant increases of micronucleated HEPs and 8-OH-dG as compared to control culture. TCDD also led to significant increases in TOS content. On the contrary, in cultures treated with DHA, the level of TAC was significantly increased during treatment in a concentration-dependent fashion. DHA showed therapeutic potential against TCDD-mediated cell viability and DNA damages. As conclusion, this study provides the first evidence that DHA has protective effects against TCDD toxicity on primary cultured rat hepatocytes.

Xanthoria elegans (Link) (lichen) extract counteracts DNA damage and oxidative stress of mitomycin C in human lymphocytes

Several lichen species have been used for medicinal purposes throughout the ages, and they are reported to be effective in the treatment of different disorders including ulcer and cancer. It is revealed that lichens may be easily accessible sources of natural drugs and possible food supplements after their safety evaluations. The main objective in this study was to evaluate the roles of aqueous extracts of Xanthoria elegans (at 25, 50 and 100 μg/ml) upon mitomycin C (MMC; at 10(-7) M) induced genotoxic and oxidative damages in cultured human lymphocytes. X. elegans were collected from the Erzurum and Artvin provinces (in Turkey) during August 2010. After the application of MMC and X. elegans extract (XEE), separate and together, human whole blood cultures were assessed by four genotoxicity end-points including chromosomal aberration, micronucleus, sister chromatid exchange (SCE) and 8-oxo-2-deoxyguanosine (8-OH-dG) assays. In addition, biochemical parameters [total antioxidant capacity (TAC) and total oxidative stress (TOS)] were examined to determine oxidative effects. According to our results, the frequencies of cytogenetic endpoints and 8-OH-dG levels were significantly increased by MMC compared with controls in human peripheral lymphocytes. MMC caused oxidative stress by altering TAC and TOS levels. On the contrary, XEE led to increases of TAC level without changing TOS level. XEE had no genotoxic effect. Furthermore, our findings revealed that MMC induced increases in the mean frequencies of four genotoxic indices were diminished by XEE in dose dependent manner, indicating its protective role towards cells from MMC exerted injury. In conclusion, the results obtained in the present study indicate for the first time that XEE is a potential source of natural antigenotoxicants.

Propolis alleviates 2,3,7,8-Tetrachlorodibenzo-p-dioxin-induced histological changes, oxidative stress and DNA damage in rat liver

2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) induces hepatic damage. Propolis exhibits antioxidant properties and several studies suggest that supplementations with antioxidants can influence hepatotoxicity. Therefore, the aim of the current study was to explore the effectiveness of propolis in alleviating the toxicity of TCDD in the liver of rats. Animals were divided into six groups, namely, TCDD (0.75 and 8 µg/kg body weight (bw)), propolis (50 mg/kg bw), TCDD (0.75 and 8 µg) plus propolis (50 mg/kg bw), and control, respectively. Rats were intraperitoneally administered with their respective doses daily for 21 days. In rats that received a high dose of TCDD, the antioxidant enzymes were significantly decreased and the serious pathological findings were established. Also, the rate of hepatocyte micronucleus (HMN) was increased after treating with TCDD. The reactions of enzymes in control and low-dose group were weak. The frequencies of HMN and liver histology were similar to both the groups. The presence of propolis with TCDD alleviated its pathological effects in hepatic tissue. Propolis also prevented the suppression of antioxidant enzymes in the livers of animals exposed to TCDD and displayed a strong protective effect against HMN. It can be concluded that propolis has beneficial influences and was able to antagonize TCDD toxicity in the liver.