Protective effect of Genistein against N-nitrosodiethylamine (NDEA)-induced hepatotoxicity in Swiss albino rats

EGF-receptor phosphorylation and downstream signaling are activated by genistein during subacute liver damage

The epidermal growth factor receptor (EGFR) plays an important role on hepatic protection in acute and chronic liver injury. The aim of this study was to investigate the role of genistein on EGFR expression, phosphorylation and signaling pathways in experimental subacute liver damage induced by carbon tetrachloride (CCl₄). We used male Wistar rats that were randomly divided into four groups: (1) Control; (2) Genistein 5 mg/kg per oral; (3) Subacute liver damage induced by CCl₄ 4 mg/kg subcutaneously; and (4) Animals received CCl₄ and genistein at the dosage indicated. The effect of genistein on EGFR expression, phosphorylation and signaling pathways were investigated by western blot and densitometric analyses. Histological changes were evaluated on slices stained with Hematoxylin-Eosin and Masson´s trichromic, as well as an immunohistochemical analysis for proliferating cell nuclear antigen (PCNA). Additionally, pro-inflammatory cytokines and liver enzymes were quantified. Our study showed that genistein increased EGFR expression, EGFR-specific tyrosine residues phosphorylation (pY1068-EGFR and pY84-EGFR), signal transducer and activator of transcription phosphorylation (pSTAT5), protein kinase B phosphorylation (pAKT) and PCNA in animals with CCl₄-induced subacute liver damage. It was found a significant reduction of pro-inflammatory cytokines in serum from animals with subacute liver damage treated with genistein. Those effects were reflected in an improvement in the architecture and liver function. In conclusion, genistein can induce a transactivation of EGFR leading to downstream cell signaling pathways as early events associated with regeneration and hepatoprotection following subacute liver damage.

[Antigenotoxicity of the soy isoflavone genistein in mice exposed to carcinogenic hexavalent chromium compounds]

Introduction

Introduction: the consumption of antioxidant-rich foods such as soy isoflavones may be an alternative in the protection and modulation against metal-induced genotoxicity with carcinogenic potential associated with oxidative stress. Objective: to evaluate the antigenotoxic effects of soy isoflavone genistein in mice exposed to carcinogenic compounds of hexavalent chromium (Cr[VI]). Material and method: twenty-five male Hsd:ICR mice were divided into five groups treated as follows: a) vehicle 1 (sterile distilled water, intraperitoneally); b) vehicle 2 (corn oil for fat-soluble compounds, orally); c) 15 mg/kg of genistein, orally; d) 20 mg/kg of CrO3, intraperitoneally; and e) 15 mg/kg of genistein four hours before the application of 20 mg/kg of CrO3. Evaluations of micronuclei (MN), apoptosis, ratio of polychromatic/normochromatic erythrocytes (EPC/ENC) and cell viability in peripheral blood obtained at 0, 24, 48 and 72 hours were performed. Results: the treatment with genistein reduced MN when administered prior to treatment with CrO3, the effect being greater at 48 hours (reduction of 84 %). Cell viability was reduced with genistein and CrO3 treatments alone, the effect being greater in the latter. Conclusions: genistein effectively blocked the genotoxic action of CrO3. The fact that MN and apoptosis were reduced in the group treated with genistein and CrO3 suggests that genistein could have inhibited the oxidative damage of Cr(VI) since, as there were no cells with damage, the apoptotic pathways were not activated.

Genistein anticancer efficacy during induced oral squamous cell carcinoma: an experimental study

BACKGROUND

About 7 million people die from various types of cancer every year representing nearly 12.5% of deaths worldwide. This fact raises the demand to develop new, effective anticancer, onco-suppressive, and chemoprotective agents for the future fighting of cancers. Genistein exhibits pleiotropic functions in cancer, metabolism, and inflammation. It functions as an antineoplastic agent through its effect on the cell cycle, apoptotic processes, angiogenesis, invasion, and metastasis.

AIM OF THE STUDY

The current study aimed to study the genistein onco-suppressive effects during 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral carcinogenesis in hamsters' buccal pouch utilizing flow cytometry analysis (FMA), as a fast-diagnosing tool, in addition to the histopathology.

MATERIAL AND METHODS

The buccal mucosa of adult male Syrian hamsters was painted with paraffin oil only (group 1), DMBA mixed in mineral oil (group 2), or orally administrated genistein along with painting DMBA (group 2B). The buccal mucosa was utilized for flow cytometric analysis and histopathological examination.

RESULTS

Grossly, DMBA-induced carcinogenesis started at the 9th week. Progressive signs appeared in the following weeks reaching to large ulcerative oral masses and exophytic nodules at the 21st week. Histologically, invasive well-differentiated oral squamous cell carcinoma (OSCC) appeared in the underlying tissues from the 12th week, showing malignant criteria. Genistein had delayed clinicopathological change, which started 6 weeks later, than the DMBA-painted hamsters, as mild epithelial dysplastic changes. This became moderate during the last 6 weeks, without dysplastic changes. Flow cytometry revealed that DMBA led to considerable variation in DNA proliferation activity, aneuploid DNA pattern, in 47.22% of hamsters and significantly raised the S-phase fragment (SPF) values, which drastically reduced after genistein treatment.

CONCLUSION

Taken together, genistein could be employed as an onco-suppressive agent for carcinogenesis. Moreover, FMA could be used as an aiding fast tool for diagnosis of cancer.

The ethnopharmacology, phytochemistry, pharmacology and toxicology of the genus Erycibe (Convolvulaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

The genus Erycibe belongs to the Convolvulaceae family that contains approximately 70 species mainly distributed from tropical and subtropical Asia to north of Australia. Several Erycibe species are traditionally used in folk medicine for the treatment of various ailments, including rheumatic arthralgia, primary glaucoma, hepatopathies, and infectious and malignant diseases.

AIM OF THE REVIEW

This review aims to summarize comprehensive and updated information on traditional medicinal uses, phytochemistry, pharmacology, and toxicology of Erycibe species to provide a reference for the further research and application of the Erycibe genus.

MATERIALS AND METHODS

The scientific and extensive literatures between 1975 and 2020 were systematically gathered from scientific databases such as SciFinder Scholar, Science Direct, Web of Science, PubMed, Google Scholar, Scopus, Springer Link and China National Knowledge Infrastructure (CNKI), as well as Chinese herbal classic books, PhD and MSc theses, and several official websites.

RESULTS

Erycibe species have been used for the treatment of various rheumatoid diseases, glaucoma, a variety of hepatic diseases, infectious diseases and various malignancies in the traditional and local medicine. Since the 1970s, 153 compounds, including coumarins, quinic acid derivatives, flavonoids, alkaloids, lignans, and others have been isolated from five species of the Erycibe genus. Pharmacological studies have shown that these extracts and compounds from the Erycibe genus have extensive activities consistent with the traditional and local applications, such as anti-glaucoma, anti-arthritic, hepatoprotective and anti-cancer activities, as well as anti-inflammatory, anti-respiratory syncytial virus (RSV), and neuroprotective properties.

CONCLUSIONS

Although there are extensive data on the genus Erycibe, certain specific gaps still exist. For herbal preparations containing Erycibe species, clinical toxicological investigation is required for the safety of these herbal preparation therapies, as well as further investigations on pharmacokinetics and bioavailability for guideline for clinical application. Furthermore, more detailed pharmacological, toxicological and clinical researches are needed to assess the alternatives to Erycibe species. Systematic and comprehensive pre-clinical studies are similarly required to estimate the possibility of extracts and compounds from the genus Erycibe with bioactivity developing into new drugs.

Genistein enhances the secretion of glucagon-like peptide-1 (GLP-1) via downregulation of inflammatory responses

Glucagon-like peptide-1 (GLP-1) an incretin hormone, is known to regulate the glucose-mediated insulin secretion. However, reduction in the level of GLP-1 is considered to be a major cause for the reduction of GLP-1-dependent insulin secretory response. Genistein an isoflavone, is an important polyphenol and has wide range of therapeutic potentials, but its therapeutic effects alone and/or in combination with metformin on GLP-1 secretion have not been investigated yet. Hence, we aimed to investigate the stimulatory action of genistein in combination with metformin on GLP-1 via downregulation of inflammatory mediators, hyperlipidemia and hyperglycemia in alloxan-induced diabetic rats. Diabetes was induced in experimental rats by single administration of alloxan intraperitoneally. Metformin (50 mg/kg/day), genistein (20 mg/kg/day) and combination of genistein and metformin was administered in alloxan-induced diabetic rats. We found that genistein alone and/or in combination with metformin significantly increased the serum level (P < 0.01) and tissue content (P < 0.05) of GLP-1 in intestine when compared with that of metformin-treated animals. Similarly, genistein alone and/or in combination with metformin also resulted in normoglycemia (P < 0.001), glucose tolerance (P < 0.01), insulin sensitivity (P < 0.0001), hyperlipidemia (P < 0.01), liver and kidney function biomarkers (P < 0.01) as compared to that of metformin-treated experimental animals. Moreover, genistein alone and/or in combination with metformin also downregulated the inflammatory responses by decreasing the levels of interleuin-6, tumor necrosis factor-α and C-reactive protein in serum (P < 0.05) and intestine (P < 0.001) more efficiently as compared to that of metformin-treated experimental animals. The downregulation of inflammatory responses in intestine, was positively associated with increased secretion of GLP-1 from intestine. Histopathology of pancreas and intestine also showed that genistein significantly improved the deleterious effects of alloxan on pancreas and intestine. Hence, our work provides new insights on the synergistic effects of genistein and metformin on GLP-1 secretion. This may significantly improve the perception for proposing new GLP-1-based synergistic approaches for the treatment of diabetes mellitus.

Genistein and Ascorbic Acid Reduce Oxidative Stress-Derived DNA Damage Induced by the Antileishmanial Meglumine Antimoniate

Meglumine antimoniate (Glucantime) is a pentavalent antimonial used to treat leishmaniasis, despite its acknowledged toxic effects, such as its ability to cause oxidative damage to lipids and proteins. Recently, our group demonstrated that meglumine antimoniate causes oxidative stress-derived DNA damage. Knowing that antioxidants modulate reactive oxygen species, we evaluated the capacity of genistein and ascorbic acid for preventing genotoxicity caused by meglumine antimoniate. For that, mice (n = 5/group) received genistein (via gavage) in doses of 5, 10, and 20 mg/kg for three consecutive days. After this period, they were treated with 810 mg/kg meglumine antimoniate via intraperitoneal (i.p.) route. Furthermore, mice (n = 5/group) simultaneously received ascorbic acid (i.p.) in doses of 30, 60, and 120 mg/kg and 810 mg/kg meglumine antimoniate. We also conducted post- and pretreatment assays, in which animals received ascorbic acid (60 mg/kg) 24 h prior to or after receiving meglumine antimoniate. Genomic instability and mutagenicity were analyzed through conventional comet assay and enzymatic assay using formamide pyrimidine DNA glycosylase (Fpg) enzyme, as well as the micronucleus test, respectively. Meglumine antimoniate induced an increase in the DNA damage after digestion with Fpg, reinforcing its mutagenic potential by oxidizing DNA bases, which was prevented by genistein. Similarly, ascorbic acid was capable of reducing mutagenic effects in simultaneous treatment as well as in posttreatment. Therefore, our results demonstrate that both compounds are efficient in preventing mutations in mammalian cells treated with meglumine antimoniate.

Diclofenac-induced renal toxicity in female Wistar albino rats is protected by the pre-treatment of aqueous leaves extract of Madhuca longifolia through suppression of inflammation, oxidative stress and cytokine formation

CONTEXT

Kidney has a vital role in renal clearance, maintenance of blood pressure, elimination of toxic products and formation of prostaglandins. Certain medications are known to cause renal injury on its frequent usage and high dosage. Diclofenac is a non-steroidal anti-inflammatory drug which is used in the treatment of pain and arthritis. Madhuca longifolia is a deciduous tree which is known to the have anti-microbial, anti-ulcer, hepatoprotective, anti-diabetic, anti-inflammatory and analgesic activity. The aim of the present study is to evaluate the beneficial effect of aqueous leaf extract of Madhuca longifolia against DFC-induced renal toxicity in female Wistar albino rats.

METHODS

Thirty female Wistar albino rats were divided into five groups and the drugs were administrated specifically on each group. After the treatment period, the rats were sacrificed to evaluate the significant changes in renal enzyme markers, antioxidant activities in kidney tissue homogenate and plasma, renal histopathology and protein expression levels. The cytokines like TNF-α, IL-6 and IL-1β were measured through ELISA techniques and the levels of Caspase-3, COX-2 and NF-κB were measured through western blotting techniques. DiscussionMadhuca longifolia was observed to show a better result in normalizing the toxicity caused by diclofenac.

CONCLUSION

The significant result of the aqueous leaf extract ofMadhuca longifolia was due to its ability in restoring renal function by restoring antioxidants and preventing cellular damages.