Biochemical and electrocardiographic studies on the beneficial effects of gallic acid in cyclophosphamide-induced cardiorenal dysfunction

Unrevealing the mechanisms behind the cardioprotective effect of wheat polyphenolics

Cardiovascular diseases pose a major threat to both life expectancy and quality of life worldwide, and a concerning level of disease burden has been attained, particularly in middle- and low-income nations. Several drugs presently in use lead to multiple adverse events. Thus, it is urgently needed to develop safe, affordable, and effective management of cardiovascular diseases. Emerging evidence reveals a positive association between polyphenol consumption and cardioprotection. Whole wheat grain and allied products are good sources of polyphenolic compounds bearing enormous cardioprotective potential. Polyphenolic extract of the entire wheat grain contains different phenolic compounds viz. ferulic acid, caffeic acid, chlorogenic acid, p-coumaric acid, sinapic acid, syringic acid, vanillic acid, apigenin, quercetin, luteolin, etc. which exert cardioprotection by reducing oxidative stress and interfering with different toxicological processes. The antioxidant capacity has been thought to exert the cardioprotective mechanism of wheat grain polyphenolics, which predominantly suppresses oxidative stress, inflammation and fibrosis by downregulating several pathogenic signaling events. However, the combined effect of polyphenolics appears to be more prominent than that of a single molecule, which might be attained due to the synergy resulting in multimodal cardioprotective benefits from multiple phenolics. The current article covers the bioaccessibility and possible effects of wheat-derived polyphenolics in protecting against several cardiovascular disorders. This review discusses the mechanistic pharmacology of individual wheat polyphenols on the cardiovascular system. It also highlights the comparative superiority of polyphenolic extracts over a single phenolic.

Suppression of glomerular damage, inflammation, apoptosis, and oxidative stress of acute kidney injury induced by cyclophosphamide toxicity using resveratrol in rat models

Cyclophosphamide (CP) is a chemotherapy drug that can be used to treat different types of cancers, but its nephrotoxicity effects restrict its usage in clinical settings. Currently, we examined whether the polyphenolic antioxidant and anti-inflammatory compound, resveratrol (RES), can protect against CP-induced nephrotoxicity. Twenty male mature Sprague-Dawley rats were divided into 4 groups of equal size: control group, RES group which received RES (20 mg/kg) for 15 consecutive days, CP group which received CP as a single dose (150 mg/kg) on day 16, and CP+RES group which was similar of the RES and CP groups. Tissue samples were obtained for the stereological, immunohistochemical, biochemical, and molecular evaluations. Findings showed that the numerical density of glomerulus, total volumes and interstitial tissue volumes of kidney, antioxidative biomarkers concentrations (CAT, GSH, SOD), and expression levels of OCT2 gene were notably greater in the CP+RES group than the CP group (P<0.05). During treatment, there was a significant decrease in the serum levels of the urea and creatinine, the densities of apoptotic and inflammatory cells, as well as levels of MDA and proinflammatory cytokines (IL-1β, TNF-α, and PFN1) in the CP+RES group than the CP group (P<0.05). We deduce that giving RES can suppress of glomerular damage, inflammation, apoptosis, and oxidative stress of acute kidney injury induced by CP toxicity.

The molecular evaluation of thioredoxin (TXN1 & TXN2), thioredoxin reductase 1 (TXNRd1), and oxidative stress markers in a binary rat model of hypo- and hyperthyroidism after treatment with gallic acid

Oxidative stress plays an important role in the pathology of thyroid disorders. This study examined the effect of gallic acid (GA) on the oxidative status and expression of liver antioxidant genes including thioredoxin (TXN1 & TXN2) and thioredoxin reductase1 (TXNRd1) in hypo- and hyperthyroid rat models. Forty-nine male Wistar rats were randomly assigned into seven groups as follows: control group, hypothyroid and hyperthyroid groups respectively induced by propylthiouracil and levothyroxine, hypo- and hyper thyroid-treated groups (where the groups were separately treated with 50 and 100 mg/kg of GA daily, orally). The levels of thyroid hormones and serum oxidative stress markers were evaluated after 5 weeks. The relative expression of TXN1,2 and TXNRd1 genes was measured via real-time qRT-PCR. The mean level of total antioxidant capacity (TAC), malondialdehyde, and uric acid index diminished in the hypothyroid group. Increased TAC reached almost the level of control in hypothyroid groups treated with GA. Elevation of thiol index in the hypothyroid group was observed (p < 0.01), which diminished to the control level after GA treatment. The relative expression of TXN1, TXNRd1, and TXN2 genes in the hypothyroid and hyperthyroid groups significantly increased compared to the control group (p ≥ 0.05), but in the groups treated with GA, the expression of these genes declined significantly (p ≥ 0.05). Our results indicated GA can affect the expression of TXN system genes in the rat liver. Also, the results suggest GA has a more positive effect on modulating serum oxidative parameters in hypothyroid rat models than in hyperthyroid.

Protective effect of Apelin-13 in a cyclophosphamide-induced cardiorenal toxicity model in rats

Cyclophosphamide is a chemotherapeutic drug that is widely used in the clinic and can cause multi-organ toxicity. Apelin-13 is an endogenous adipocytokine with antioxidant properties. Therefore, this study aimed to investigate the possibility of apelin-13 being a potential therapeutic agent on cardiac toxicity and nephrotoxicity caused by cyclophosphamide. In this study, a total of 4 groups were formed, including 8 rats in each group. Group 1: The control group was administered only saline (ip). Group 2: Cyclophosphamide, a single dose of 200 mg/kg (ip) on day 7. Group 3: Apelin-13 (15 μg/kg), for 7 days (ip). Group 4: Administering apelin-13 (15 μg/kg) (ip) for 7 days and a single dose of cyclophosphamide (200 mg/kg) (ip) on day 7, the rats were sacrificed on day 8. LDH, cTn1, cK-Mb, AST, ALT, ALP, MDA, creatinine, and BUN were found to be high in the cyclophosphamide group, however, these values were reduced with apelin-13 administration. Antioxidant enzymes such as SOD, GPx, CAT, and GSH decreased in the cyclophosphamide group, apelin-13 increased these enzyme activities. In addition, histopathological examinations also supported the results obtained. The findings of this study showed that apelin-13 has a protective effect against cardiorenal toxicity caused by cyclophosphamide.

Cardioprotective Effect of Crude Extract and Solvent Fractions of Urtica simensis Leaves on Cyclophosphamide-Induced Myocardial Injury in Rats

Background

Globally, cardiovascular diseases (CVDs) are becoming the major cause of death. Urtica simensis is one of endogenous plant which treats a wide range of disease conditions including heart diseases. However, there is limited information on safety and efficacy of the plant.

Objective

To evaluate the in vitro antioxidant, the in vivo cardioprotective activity of crude extract and solvent fractions of Urtica simensis leaves on cyclophosphamide-induced myocardial injury.

Methods

The cardioprotective activity of the crude extract, aqueous and hexane fraction of Urtica simensis leaves was evaluated based on anatomical, biochemical and histopathological methods. The in vitro antioxidant activity of the plant was also assayed in terms of free radical scavenging activity (RSA).

Results

Crude extract and solvent fractions of Urtica simensis significantly prevented the deleterious effect of cyclophosphamide on body weight (P<0.001), heart weight to body ratio (P<0.01), cardiac biomarkers including troponin I (P<0.01), alanine transaminase (ALT) (P<0.001), aspartate aminotransferase (AST) (P<0.01) and lipid profiles including triglycerides (P<0.001) and total cholesterol (P<0.01). The histopathological study confirmed presence of necrosis, oedema and haemorrhage on cyclophosphamide alone-treated groups while the 200mg/kg and 400mg/kg of the crude extract and aqueous fraction showed normal cardiocytes. The antioxidant assay of Urtica simensis plant exhibited free radical scavenging activity of inhibitory concentration of 50% (IC₅₀) for the crude extract with the values of 63.27µg/mL, aqueous fraction with the values of 136.38µg/mL and hexane fraction with the values of 258.70µg/mL.

Conclusion

Crude extract and solvent fractions of Urtica simensis leaves have cardioprotective activities. The cardioprotective effect could be attributed to the antioxidant activity of the plant extracts. However, this requires further in-depth understanding.

Methyl Gallate Attenuates Doxorubicin-Induced Cardiotoxicity in Rats by Suppressing Oxidative Stress

Doxorubicin-induced cardiotoxicity is the leading cause of morbidity and mortality among cancer survivors. The present study was aimed to investigate the cardioprotective potential of methyl gallate; an active polyphenolic nutraceutical, against doxorubicin-induced cardiotoxicity in Wistar rats. Twenty-four female Wistar rats (150-200 g) were divided into four groups (n = 6) which consist of normal control (group I), doxorubicin control (group II), test-A (group III), and test-B (group IV). Group III and group IV animals were prophylactically treated with methyl gallate 150 mg/kg/day and 300 mg/kg/day orally, respectively, for seven days. Doxorubicin (25 mg/kg; single dose) was administered through an intraperitoneal route to group II, III, and IV animals on the seventh day to induce acute cardiotoxicity. On the 8^th day, besides ECG analysis, serum CK, CK-MB, LDH, AST, MDA, and GSH were assayed. Following gross examination of isolated hearts, histopathological evaluation was performed by light microscopy. A significant (p < 0.05) cardiac injury, as well as oxidative stress, was observed in doxorubicin control rats in comparison to normal control rats. Methyl gallate at both the doses significantly (p < 0.05) reduced doxorubicin-induced ECG changes, dyslipidaemia, and elevation of CK, CK-MB, LDH, AST, MDA and increased GSH level. Methyl gallate reversed the doxorubicin-induced histopathological changes in the heart. The present study revealed that methyl gallate exerts cardioprotection against doxorubicin-induced cardiotoxicity in female Wistar rats by suppressing oxidative stress. Our study opens the perspective to clinical studies for consideration of methyl gallate as a potential chemoprotectant nutraceutical in the combination chemotherapy with doxorubicin to limit its cardiotoxicity.

Protective Effect of Croton macrostachyus (Euphorbiaceae) Stem Bark on Cyclophosphamide-Induced Nephrotoxicity in Rats

Background

Cyclophosphamide is an alkylating antineoplastic agent and its major limitation is injury to normal tissue, leading to multiple organ toxicity, including kidney, heart, liver and reproductive toxicity. Croton macrostachyus (Euphorbiaceae) has been used in Ethiopian traditional medicine to manage renal diseases.

Objective

The present study aims to assess the protective effect of the stem bark extract and solvent fractions of Croton macrostachyus on cyclophosphamide-induced nephrotoxicity in rats.

Methods

Nephrotoxicity was induced using cyclophosphamide 200 mg/kg i.p injection on the first day of the experiment. The negative control groups were administered with cyclophosphamide alone (200 mg/kg, i.p.). The crude extracts were administered at three dose levels (100, 200, and 400 mg/kg), while aqueous and ethyl acetate fractions were given at two dose levels (100 and 200 mg/kg). Excepting the normal control, all groups were subjected to cyclophosphamide toxicity on the first day.

Results

Treatment with crude extract 100 mg/kg and ethyl acetate fraction significantly decreased kidney-to-body weight ratio (P < 0.001). In addition, treatment with Croton macrostachyus crude extract and solvent fractions significantly decreased serum blood urea nitrogen (BUN) level (P < 0.001). Treatment with 100 and 200 mg/kg of ethyl acetate fraction significantly decreased serum creatinine level. Histopathological results confirmed the protective effect of the crude extract and solvent fractions of Croton macrostachyus.

Conclusion

Croton macrostachyus possesses nephroprotective activities and it could be a possible source of treatment for cyclophosphamide-induced nephrotoxicity.

Cardioprotective Effect of Croton macrostachyus Stem Bark Extract and Solvent Fractions on Cyclophosphamide-Induced Cardiotoxicity in Rats

Objective

To evaluate the antioxidant and cardioprotective activities of stem bark extract and solvent fractions of Croton macrostachyus on cyclophosphamide-induced cardiotoxicity in rats. Materials and Methods. DPPH free radical scavenging assay method was used to determine antioxidant activity whereas Sprague-Dawley rats were used to evaluate the cardioprotective activity. Except for the normal control, all groups were subjected to cyclophosphamide (200 mg/kg, i.p.) toxicity on the first day. Enalapril at 10 mg/kg was used as a reference. The hydromethanolic crude extract (100, 200, and 400 mg/kg) and aqueous and ethyl acetate fractions (100 and 200 mg/kg, each) were administered for 10 days. The cardioprotective activities were evaluated using cardiac biomarkers such as Troponin I, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total cholesterol (TC), triglyceride (TG), and histopathological studies of heart tissue.

Results

Crude extract and ethyl acetate and aqueous fractions exhibited free radical scavenging activities at IC₅₀ of 594 μg/mL, 419 μg/mL, and 716 μg/mL, respectively. Crude extract at 400 mg/kg decreased the levels of troponin, AST, ALT, and ALP to 0.29 ± 0.06 ng/mL, 103.00 ± 7.63 U/L, 99.80 ± 6.18 U/L, and 108.80 ± 8.81 U/L, respectively. In addition, ethyl acetate fraction at 200 mg/kg decreased the levels of troponin, AST, ALT, and ALP to 0.22 ± 0.02 ng/mL, 137.00 ± 14.30 U/L, 90.33 ± 6.13 U/L, and 166.67 ± 13.50 U/L, respectively, compared with the cyclophosphamide control group.

Conclusions

Croton macrostachyus possesses cardioprotective activities and it could be a possible source of treatment for cardiotoxicity induced by cyclophosphamide.

A Role of Gallic Acid in Oxidative Damage Diseases: A Comprehensive Review

Gallic acid is a trihydroxybenzoic acid of plant metabolites widely spread throughout the plant kingdom. It has characteristics of the strong antioxidant and free radical scavenging activities, and can protect biological cells, tissues, and organs from damages caused by oxidative stress. This review aims to summarize the protective roles of gallic acid and the underlying pharmacological mechanisms in the pathophysiological process of the oxidative damage diseases, such as cancer, cardiovascular, degenerative, and metabolic diseases. The studies reviewed herein showed that the main therapeutic effects of gallic acid were attributed to its antioxidant properties. It modulated various signaling pathways through a wide range of inflammatory cytokines, and enzymic and nonenzymic antioxidants. However, the available data were limited to few studies assessing the treatment effects of gallic acid in human subjects to confirm its therapeutic outcomes. Therefore, the clinical trials were urgently needed to investigate the safety and efficacy of gallic acid treatment on human beings. The scientific data summarized in this review highlighted the therapeutic potentials of gallic acid for oxidative damage diseases. It could be developed as versatile adjuvant or therapeutically lead compound in future.

Protective effect of some natural products against chemotherapy-induced toxicity in rats

Aim

There is a great interest in combining anticancer drugs with natural products aiming at maximizing their efficacy while minimizing systemic toxicity. Hence, the present study was constructed aiming to investigate the protective potential of three natural products, 1,8-cineole an essential oil from Artemisia herba alba, exopolysaccharide (EPS) from locally identified marine streptomycete, and ellagic acid (EA), against chemotherapy-induced organ toxicity.

Methods

Isolation, production and characterization of EPS from marine streptomycete was done. Animals were allocated into five groups, GP1: normal control, GP2: cyclophosphamide (CYC), GP3: 1,8-cineole + CYC, GP4: EPS + CYC, GP4: EA + CYC. All drugs were administered orally 1 week before and concomitantly with CYC. Electrocardiography (ECG) analysis, liver enzymes (ALT and AST), cardiac serum markers (LDH and CK), oxidative stress biomarkers in hepatic and cardiac tissues (GSH and MDA), TGF-β1 and histopathological examination of hepatic and cardiac tissues were executed.

Results

The isolated stain produced EPS was identified as Streptomyces xiamenensis. EPS contains uronic, sulphate groups and different monosugars with Mw 4.65 × 10⁴ g/mol and showed antioxidant activity against DPPH. Pretreatment of rats with 1,8-cineole, EPS and EA improved ECG abnormalities, decrease serum markers of hepato- and cardiotoxicity, prevent oxidative stress and decrease TGF-β1 in liver and heart tissues.

Conclusion

The present results demonstrate the hepatoprotective and cardioprotective effects of the above-mentioned natural products against CYC organ toxicity.

Pharmacological effects of gallic acid in health and diseases: A mechanistic review

OBJECTIVES

Gallic acid is a natural phenolic compound found in several fruits and medicinal plants. It is reported to have several health-promoting effects. This review aims to summarize the pharmacological and biological activities of gallic acid in vitro and animal models to depict the pharmacological status of this compound for future studies.

MATERIALS AND METHODS

All relevant papers in the English language were collected up to June 2018. The keywords of gallic acid, antioxidant, anticancer, antimicrobial, gastrointestinal-, cardiovascular-, metabolic-, neuropsychological-, and miscellaneous- diseases were searched in Google Scholar, PubMed, and Scopus.

RESULTS

Several beneficial effects are reported for gallic acid, including antioxidant, anti-inflammatory, and antineoplastic properties. This compound has been reported to have therapeutic activities in gastrointestinal, neuropsychological, metabolic, and cardiovascular disorders.

CONCLUSION

Current evidence confirms the pharmacological and therapeutic interventions of gallic acid in multiple health complications; however, available data are limited to just cellular and animal studies. Future investigations are essential to further define the safety and therapeutic efficacy of gallic acid in humans.

Gallic acid improves cardiac dysfunction and fibrosis in pressure overload-induced heart failure

Gallic acid is a trihydroxybenzoic acid found in tea leaves and some plants. Here, we report the effect of gallic acid on cardiac dysfunction and fibrosis in a mouse model of pressure overload-induced heart failure and in primary rat cardiac fibroblasts, and compare the effects of gallic acid with those of drugs used in clinics. Gallic acid reduces cardiac hypertrophy, dysfunction, and fibrosis induced by transverse aortic constriction (TAC) stimuli in vivo and transforming growth factor β1 (TGF-β1) in vitro. It decreases left ventricular end-diastolic and end-systolic diameter, and recovers the reduced fractional shortening in TAC. In addition, it suppresses the expression of atrial natriuretic peptide, brain natriuretic peptide, skeletal α-actin, and β-myosin heavy chain. Administration of gallic acid decreases perivascular fibrosis, as determined by Trichrome II Blue staining, and reduces the expression of collagen type I and connective tissue growth factor. However, administration of losartan, carvedilol, and furosemide does not reduce cardiac dysfunction and fibrosis in TAC. Moreover, treatment with gallic acid inhibits fibrosis-related genes and deposition of collagen type I in TGF-β1-treated cardiac fibroblasts. These results suggest that gallic acid is a therapeutic agent for cardiac dysfunction and fibrosis in chronic heart failure.

Antidepressant-like effect of gallic acid in mice: Dual involvement of serotonergic and catecholaminergic systems

AIMS

This study was planned to examine the antidepressant potency of gallic acid (30 and 60mg/kg), a phenolic acid widely distributed in nature, together with its possible underlying monoaminergic mechanisms.

MAIN METHODS

Antidepressant-like activity was assessed using the tail suspension (TST) and the modified forced swimming tests (MFST). Locomotor activity was evaluated in an activity cage.

KEY FINDINGS

Administration of gallic acid at 60mg/kg reduced the immobility duration of mice in both the TST and MFST without any changes in the locomotor activity. The anti-immobility effect observed in the TST was abolished with pre-treatment of p-chlorophenylalanine methyl ester (an inhibitor of serotonin synthesis; 100mg/kg i.p. administered for 4-consecutive days), ketanserin (a 5-HT2A/2C antagonist; 1mg/kg i.p.), ondansetron (a 5-HT3 antagonist; 0.3mg/kg i.p.), α-methyl-para-tyrosine methyl ester (an inhibitor of catecholamine synthesis; 100mg/kg i.p.), phentolamine (non-selective alpha-adrenoceptor antagonist; 5mg/kg i.p.), SCH 23390 (a dopamine D1 antagonist; 0.05mg/kg s.c.), and sulpiride (a dopamine D2/D3 antagonist; 50mg/kg i.p.). However, NAN 190 (a 5-HT1A antagonist; 0.5mg/kg i.p.) and propranolol (a non-selective β-adrenoceptor antagonist; 5mg/kg i.p.) pre-treatments were ineffective at reversing the antidepressant-like effects of gallic acid.

SIGNIFICANCE

The results of the present study indicate that gallic acid seems to have a dual mechanism of action by increasing not only serotonin but also catecholamine levels in synaptic clefts of the central nervous system. Further alpha adrenergic, 5-HT2A/2C and 5-HT3 serotonergic, and D1, D2, and D3 dopaminergic receptors also seem to be involved in this antidepressant-like activity.