Amelioration of Isoproterenol-Induced Oxidative Damage in Rat Myocardium by Withania somnifera Leaf Extract

Date Palm (Phoenix dactylifera) Fruits as a Potential Cardioprotective Agent: The Role of Circulating Progenitor Cells

Context: Date palms, along with their fruits’ dietary consumption, possess enormous medicinal and pharmacological activities manifested in their usage in a variety of ailments in the various traditional systems of medicine. In recent years, the identification of progenitor cells in the adult organ systems has opened an altogether new approach to therapeutics, due to the ability of these cells to repair the damaged cells/tissues. Hence, the concept of developing therapeutics, which can mobilize endogenous progenitor cells, following tissue injury, to enhance tissue repair process is clinically relevant.

Objectives: The present study investigates the potential of date of palm fruit extracts in repairing tissue injury following myocardial infarction (MI) potentially by mobilizing circulating progenitor cells.

Methods: Extracts of four different varieties of date palm fruits common in Saudi Arabia eastern provision were scrutinized for their total flavonoid, total phenolic, in vitro antioxidant capacity, as well as their effects on two different rodent MI models.

Results: High concentrations of phenolic and flavonoid compounds were observed in date palm fruit extracts, which contributed to the promising antioxidant activities of these extracts and the observed high protective effect against various induced in vivo MI. The extracts showed ability to build up reserves and to mobilize circulating progenitor cells from bone marrow and peripheral circulation to the site of myocardial infraction.

Conclusion: Date palm fruit extracts have the potential to mobilize endogenous circulating progenitor cells, which can promote tissue repair following ischemic injury.

In vivo ameliorative effect of cerium oxide nanoparticles in isoproterenol-induced cardiac toxicity

BACKGROUND

Cerium oxide nanoparticles have gained much more attention especially in the field of nanomedicine. This work represents cerium oxide nanoparticles as a new prophylactic model for heart failure progression.

OBJECTIVE

To investigate the potential protective effect of cerium oxide nanoparticles on Isoproterenol (ISO)-induced cardiac toxicity in rats.

METHODS

Cerium oxide nanoparticles (5±1nm) were synthesized by reverse micelle method and characterized using High Resolution Transmission Electron Microscopy, X-Ray Diffraction and particle size analyzer. The experiments were performed on 96 male Wistar rats. The rats were randomly allocated into eight groups. Namely; two Negative and positive control groups, captopril administered group, Nano-ceria (low dose) group, Nano-ceria (high dose) group, Captopril- Isoproterenol group, Nano-ceria (low dose)-Isoproterenol group and Nano-ceria (high dose)-Isoproterenol group. Cardio toxic rat model was induced by subcutaneous administration of Isoproterenol (ISO) (30mg/kg) for two consecutive days in adult male rats. Two doses (0.5 and 5μg/kg/week) of cerium oxide nanoparticles were applied for five weeks and 50mg/kg/day of Captopril was used as a reference drug. Cardiac marker enzymes, Cortisol and Aldosterone hormones were assessed in serum. Oxidant-antioxidant parameters and histopathological examination in heart tissues were also determined.

RESULTS

These dose of nano-ceria, showed a promising ameliorative and prophylactic effect against cardiac toxicity compared to Captopril reference drug. Serum cardiac markers were decreased by noticeable percentage, CK-MB (50% and 57%), LDH (47% and 57.7%), AST (38% and 36.5%) and ALT (33.5% and 30.6%) for both doses respectively, while increased tissues level of the antioxidant enzymes, catalase (48% - 26%) and superoxide dismutase (64%, 143%).

CONCLUSION

These consistent biochemical and histopathological results suggest that, nano-ceria could be used as effective antioxidant in prophylactic protocols for management of cardiac disorders associated with oxidative stress.

Protective effect of Azolla microphylla on biochemical, histopathological and molecular changes induced by isoproterenol in rats

Azolla microphylla is an important fast-growing aquatic plant trusted for its agronomic, nutritious and therapeutic uses. The present work is undertaken to investigate the protective effect of the ethanolic extract of Azolla microphylla (EAM) against the Isoproterenol (ISO) induced cardiotoxicity in rats. Rats were pre-treated with EAM (250 and 500mg/kg b.w.) for 28 days along with ISO (85mg/kg; s.c.) on the 29th and 30th days. ISO-induced rats displayed significant diminution in cardiac antioxidant enzymes activities, increased lipid peroxidation and alteration in cardiac marker enzymes. The same group also displayed an increase in levels of serum lipid profiles and pro-inflammatory cytokines (IL-6 and IL-8) accompanied with a significant reduction in the anti-inflammatory cytokine levels (IL-10). Moreover, the histopathological investigations in the heart tissue of ISO-induced group exhibited myocardial necrosis and inflammation, which correlated with the increased immunoreactivity for Bax/iNOS, whereas an absence of reactivity for Bcl-2 proteins. However, in EAM pre-treated rats, the activities of antioxidant enzymes, cardiac marker enzymes, membrane-bound ATPases together with the levels of lipid profile, non-enzymatic antioxidants, pro and anti-inflammatory cytokines were maintained at normalcy that was further supported by improving histopathological changes and myocardial architecture. The IHC results of EAM pre-treated rats indicate up-regulated and down-regulated expressions of Bcl-2 and Bax/iNOS proteins, respectively. Thus, the present study reveals that A. microphylla alleviates myocardial damage in ISO-induced cardiac injury and demonstrates cardioprotective potential which could be attributed to its potent antioxidant and free radical scavenging activity. A possible mechanism for the protective effect is the elevated expression of endogenous antioxidant defense enzymes, anti-inflammatory cytokines, degraded lipid peroxidation products and improved energy metabolism of cardiac mitochondria, thus attenuating necrosis of the myocytes.

Antioxidant Properties and Cardioprotective Mechanism of Malaysian Propolis in Rats

Propolis contains high concentrations of polyphenols, flavonoids, tannins, ascorbic acid, and reducing sugars and proteins. Malaysian Propolis (MP) has been reported to exhibit high 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging activity and ferric reducing antioxidant power (FRAP) values. Herein, we report the antioxidant properties and cardioprotective properties of MP in isoproterenol- (ISO-) induced myocardial infarction in rats. Male Wistar rats (n = 32) were pretreated orally with an ethanol extract of MP (100 mg/kg/day) for 30 consecutive days. Subcutaneous injection of ISO (85 mg/kg in saline) for two consecutive days caused a significant increase in serum cardiac marker enzymes and cardiac troponin I levels and altered serum lipid profiles. In addition significantly increased lipid peroxides and decreased activities of cellular antioxidant defense enzymes were observed in the myocardium. However, pretreatment of ischemic rats with MP ameliorated the biochemical parameters, indicating the protective effect of MP against ISO-induced ischemia in rats. Histopathological findings obtained for the myocardium further confirmed the biochemical findings. It is concluded that MP exhibits cardioprotective activity against ISO-induced oxidative stress through its direct cytotoxic radical-scavenging activities. It is also plausible that MP contributed to endogenous antioxidant enzyme activity via inhibition of lipid peroxidation.

Natural product HTP screening for attenuation of cytokine-induced neutrophil chemo attractants (CINCs) and NO2- in LPS/IFNγ activated glioma cells

Chronic and acute central nervous system (CNS) inflammation are contributors toward neurological injury associated with head trauma, stroke, infection, Parkinsons or Alzheimers disease. CNS inflammatory illnesses can also contribute toward risk of developing glioblastoma multiforme (GBM). With growing public interest in complementary and alternative medicines (CAMs), we conduct a high throughput (HTP) screening of >1400 natural herbs, plants and over the counter (OTC) products for anti-inflammatory effects on lipopolysaccharide (LPS)/interferon gamma (IFNγ) activated C6 glioma cells. Validation studies were performed showing a pro-inflammatory profile of [LPS 3 µg/ml/ IFNγ 3 ng/ml] consistent with greater release [>8.5 fold] of MCP-1, NO2-, cytokine-induced neutrophil chemo-attractants (CINC) 1, CINC 2a and CINC3. The data show no changes to the following, IL-13, TNF-a, fracktaline, leptin, LIX, GM-CSF, ICAM1, L-Selectin, activin A, agrin, IL-1α, MIP-3a, B72/CD86, NGF, IL-1b, MMP-8, IL-1 R6, PDGF-AA, IL-2, IL-4, prolactin R, RAGE, IL-6, Thymus Chemokine-1, CNTF,IL-10 or TIMP-1. A HTP screening was conducted, where we employ an in vitro efficacy index (iEI) defined as the ratio of toxicity (LC₅₀)/anti-inflammatory potency (IC₅₀). The iEI was precautionary to ensure biological effects were occurring in fully viable cells (ratio > 3.8) independent of toxicity. Using NO2- as a guideline molecule, the data show that 1.77% (25 of 1410 tested) had anti-inflammatory effects with iEI ratios >3.8 and IC₅₀s <250µg/ml. These include reference drugs (hydrocortisone, dexamethasone N6-(1-iminoethyl)-l-lysine and NSAIDS: diclofenac, tolfenamic acid), a histone deacetylase inhibitor (apicidin) and the following natural products; Ashwaganda (Withania somnifera), Elecampagne Root (Inula helenium), Feverfew (Tanacetum parthenium), Green Tea (Camellia sinensis), Turmeric Root (Curcuma longa) Ganthoda (Valeriana wallichii), Tansy (Tanacetum vulgare), Maddar Root (Rubia tinctoria), Red Sandle wood (Pterocarpus santalinus), Bay Leaf (Laurus nobilis, Lauraceae), quercetin, cardamonin, fisetin, EGCG, biochanin A, galangin, apigenin and curcumin. The herb with the largest iEI was Ashwaganda where the IC₅₀/LC₅₀ was 11.1/>1750.0μg/ml, and the compound with the greatest iEI was quercetin where the IC₅₀/LC₅₀ was 10.0/>363.6μg/ml. These substances also downregulate the production of iNOS expression and attenuate CINC-3 release. In summary, this HTP screening provides guideline information about the efficacy of natural products that could prevent inflammatory processes associated with neurodegenerative disease and aggressive glioma tumor growth.

Natural product HTP screening for antibacterial (E.coli 0157:H7) and anti-inflammatory agents in (LPS from E. coli O111:B4) activated macrophages and microglial cells; focus on sepsis

Background

Acute systemic inflammatory response syndrome arising from infection can lead to multiple organ failure and death, with greater susceptibility occurring in immunocompromised individuals. Moreover, sub-acute chronic inflammation is a contributor to the pathology of diverse degenerative diseases (Parkinson’s disease, Alzheimer’s disease and arthritis). Given the known limitations in Western medicine to treat a broad range of inflammatory related illness as well as the emergence of antibiotic resistance, there is a renewed interest in complementary and alternative medicines (CAMs) to achieve these means.

Methods

A high throughput (HTP) screening of >1400 commonly sold natural products (bulk herbs, cooking spices, teas, leaves, supplement components, nutraceutical food components, fruit and vegetables, rinds, seeds, polyphenolics etc.) was conducted to elucidate anti-inflammatory substances in lipopolysaccharide (LPS) (E. coli serotype O111:B4) monocytes: RAW 264.7 macrophages [peripheral], BV-2 microglia [brain]) relative to hydrocortisone, dexamethasone and L-N6-(1Iminoethyl)lysine (L-NIL). HTP evaluation was also carried out for lethal kill curves against E.coli 0157:H7 1x10⁶ CFU/mL relative to penicillin. Validation studies were performed to assess cytokine profiling using antibody arrays. Findings were corroborated by independent ELISAs and NO2–/iNOS expression quantified using the Griess Reagent and immunocytochemistry, respectively. For robust screening, we developed an in-vitro efficacy paradigm to ensure anti-inflammatory parameters were observed independent of cytotoxicity. This caution was taken given that many plants exert tumoricidal and anti-inflammatory effects at close range through similar signaling pathways, which could lead to false positives.

Results

The data show that activated BV-2 microglia cells (+ LPS 1μg/ml) release >10-fold greater IL-6, MIP1/2, RANTES and nitric oxide (NO2–), where RAW 264.7 macrophages (+ LPS 1μg/ml) produced > 10-fold rise in sTNFR2, MCP-1, IL-6, GCSF, RANTES and NO2–. Data validation studies establish hydrocortisone and dexamethasone as suppressing multiple pro-inflammatory processes, where L-NIL suppressed NO2–, but had no effect on iNOS expression or IL-6. The screening results demonstrate relative few valid hits with anti-inflammatory effects at < 250μg/ml for the following: Bay Leaf (Laurus nobilis), Elecampagne Root (Inula helenium), Tansy (Tanacetum vulgare),Yerba (Eriodictyon californicum) and Centipeda (Centipeda minima), Ashwagandha (Withania somnifera), Feverfew (Tanacetum parthenium), Rosemary (Rosmarinus officinalis), Turmeric Root (Curcuma Longa), Osha Root (Ligusticum porteri), Green Tea (Camellia sinensis) and constituents: cardamonin, apigenin, quercetin, biochanin A, eupatorin, (-)-epigallocatechin gallate (EGCG) and butein. Natural products lethal against [E. coli 0157:H7] where the LC₅₀ < 100 μg/ml included bioactive silver hydrosol-Argentyn 23, green tea (its constituents EGCG > Polyphenon 60 > (-)-Gallocatechin > Epicatechin > (+)-Catechin), Grapeseed Extract (Vitis vinifera), Chinese Gallnut (its constituents gallic acid > caffeic acid) and gallic acid containing plants such as Babul Chall Bark (Acacia Arabica), Arjun (Terminalia Arjuna) and Bayberry Root Bark (Morella Cerifera).

Conclusions

These findings emphasize and validate the previous work of others and identify the most effective CAM anti-inflammatory, antibacterial compounds using these models. Future work will be required to evaluate potential combination strategies for long-term use to prevent chronic inflammation and possibly lower the risk of sepsis in immunocompromised at risk populations.

Sundarban Honey Confers Protection against Isoproterenol-Induced Myocardial Infarction in Wistar Rats

The present study was designed to investigate the cardioprotective effects of Sundarban honey (SH) in rats with isoproterenol- (ISO-) induced myocardial infarction. Adult male Wistar Albino rats were pretreated with Sundarban honey (5 g/kg) daily for a period of 6 weeks. After the treatment period, ISO (85 mg/kg) was subcutaneously injected into the rats at 24 h intervals for 2 days. ISO-induced myocardial damage was indicated by increased serum cardiac specific troponin I levels and cardiac marker enzyme activities including creatine kinase-MB, lactate dehydrogenase, aspartate transaminase, and alanine transaminase. Significant increases in serum total cholesterol, triglycerides, and low-density lipoprotein-cholesterol levels were also observed, along with a reduction in the serum high-density lipoprotein-cholesterol level. In addition to these diagnostic markers, the levels of lipid peroxide products were significantly increased. The activities of antioxidant enzymes such as superoxide dismutase, glutathione peroxidase, and glutathione reductase were significantly decreased in the hearts after ISO-induced myocardial infarction. However, pretreatment of ischemic rats with Sundarban honey brought the biochemical parameters to near normalcy, indicating the protective effect of Sundarban honey against ISO-induced ischemia in rats. Histopathological findings of the heart tissues further confirmed the biochemical findings, indicating that Sundarban honey confers protection against ISO-induced oxidative stress in the myocardium.