Abstract PD17-12: Primary efficacy and safety results from the AMALEE trial evaluating 600 mg vs 400 mg starting doses of first-line ribociclib in patients with HR+/HER2− advanced breast cancer

Background: In the Phase III MONALEESA (ML)-2, -3 and -7 trials, a 600 mg dose of ribociclib (RIB) demonstrated significant overall survival benefit in patients (pts) with HR+/HER2− advanced breast cancer (ABC) but was associated with QTcF (>480 ms, 3%-7%) and neutropenia (G3/4, 57%-64%) adverse events (AEs) which were managed by dose reductions. The Phase II AMALEE study was performed as a postmarketing commitment to assess whether reducing the starting dose of RIB from the recommended dose (3 wk on, 1 wk off) of 600 mg/day to 400 mg/day decreases QTcF prolongation without compromising the efficacy of first-line RIB in pts with HR+/HER2− ABC. Here, we present efficacy and safety results from the primary analysis of AMALEE. Methods: AMALEE is a randomized Phase II open-label study including pre- and postmenopausal pts with HR+/HER2− ABC with no prior therapy for ABC. Pts received RIB 400 mg + nonsteroidal aromatase inhibitor (NSAI) or RIB 600 mg + NSAI. The primary endpoint is to determine whether overall response rate (ORR) in the 400 mg arm is noninferior to the 600 mg arm. The key secondary endpoint is QTcF prolongation at cycle 1, day 15 (C1D15) 2 hours post dose. Additional endpoints included safety, progression-free survival (PFS), duration of response (DOR), time to response (TTR), and pharmacokinetics. Results: A total of 376 pts were randomized 1:1 to receive RIB at either 400 mg or 600 mg doses. Baseline (BL) characteristics and prior antineoplastic therapy were balanced across treatment (tx) arms. At the time of the data cutoff (June 11, 2021), median follow-up was 14.9 mo (min, 6.1; max, 23.8), and all pts had been treated for ≥6 months from randomization or had discontinued study tx. ORR for RIB was 41.5% (95% CI, 34.4-48.7) with 400 mg vs 45.3% (95% CI, 38.1-52.6) with 600 mg (ORR ratio for RIB 400 mg vs 600 mg, 0.921 [90% CI, 0.757-1.121]). The lower 90% CI boundary did not meet the prespecified noninferiority (NI) margin of 0.814. Results for ORR by subgroups were consistent with the overall analysis set. RIB plasma exposure was lower at 400 mg than 600 mg; the geometric mean Cmax and AUC0-24h at C1D15 were approximately 28% and 43% lower in the 400 mg than the 600 mg arm (Cmax 1080 vs 1500 ng/mL and AUC0-24h 16400 vs 28600 ng × h/mL). This study met the key secondary endpoint, change in QTcF at C1D15 in the RIB 400 mg group with a 90% CI upper boundary of < 20 ms. Mean change in QTcF from BL to C1D15 2 hours post dose was lower in the 400 mg (12.5 ms, 90% CI, 10.9-14.1) than the 600 mg arm (19.7 ms, 90% CI, 17.4-22.0). QTcF ≥501 ms occurred in 1.6% of pts in the 400 mg arm vs 0.5% in the 600 mg arm. Rates of G3/4 neutropenia were lower in the 400 mg (31.4%) than the 600 mg arm (46.3%). Other safety results were consistent with those previously reported for RIB in the ML trials. Median duration of exposure to RIB was 8.0 mo (min, 0.1; max, 23.7) in the 400 mg arm vs 8.8 mo (min, 0.5; max, 20.8) in the 600 mg arm. Dose reductions of RIB were more frequent in the 600 mg group with 30.5% vs 13.8% of pts requiring 1 dose reduction in the 600 mg and 400 mg groups, respectively. Dose reductions were primarily attributable to AEs, with neutropenia being the most frequently reported AE requiring a dose modification. Rates of discontinuation due to AEs were similar in the 400 mg vs 600 mg arms (8.5% vs 9.6%). PFS, DOR, and TTR data are currently immature. Conclusions: RIB at the 400 mg dose shows a better safety profile vs 600 mg in terms of key AEs that are RIB concentration dependent (neutropenia and QTcF prolongation). ORR was 3.8% lower with 400 mg than 600 mg. The lower 90% CI boundary of the ORR ratio did not meet the NI margin, thus this study was unable to demonstrate statistical NI of the 400 mg vs 600 mg dose of RIB using ORR as the endpoint. Updated results with additional follow-up and the clinically relevant endpoint PFS will be presented at the congress.

Citation Format: Fatima Cardoso, William Jacot, Sherko Küemmel, Sudeep Gupta, Rama Balaraman, Liudmila Lebedeva, Yan Ji, Aparna Lakshmanan, Khalid Amin, Zheng Li, Joseph Sparano. Primary efficacy and safety results from the AMALEE trial evaluating 600 mg vs 400 mg starting doses of first-line ribociclib in patients with HR+/HER2− advanced breast cancer [abstract]. In: Proceedings of the 2022 San Antonio Breast Cancer Symposium; 2022 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2023;83(5 Suppl):Abstract nr PD17-12.

Short Term Follow Up of Patients with Osteoporotic Vertebral Compression Fractures Treated with Percutaneous Vertebroplasty

Vertebral compression fractures are the most common osteoporotic fractures, 30-50% of all women develop vertebral compression fractures. In this study the mean age of 64 years with youngest case of age of 55 years and oldest case. 55 % of patients included in the study are female. One case had systemic hypertension, one case had Parkinsonism, and one case had Coronary Artery Disease. A significant reduction in analgesic intake was revealed. The patients without any analgesics increased from 0.5% (n=2) pre operative to 85.7% (n=30) at the six months follow-up (P less than 0.0001). pain score of ODS for immediate, 1month, 2 month, 3rd month and 6 month and found that(patient active measure) pam is reduced after immediate to 1 month till 6 month(p<0.05), and after 3 rd month to 6 month no difference in pam score was observed.

Assessment of Aliskiren Hemifumarate and Amlodipine Besylate in combined Tablet Dosage form by Three Simple UV Spectrophotometric Methods

Background: For a cardiovascular patient's blood pressure to be effectively controlled, more than one drug is required. When coupled with amlodipine besylate (AMLO), a calcium channel blocker, Aliskiren hemifumarate (ALI) is the 1st nonpeptide, low molecular mass, orally active transition state rennin inhibitor to efficaciously normalize blood pressure and cardiac ailments. Objective: Three innovative, easy, sensitive, exact, and accurate UV spectrophotometric approaches, including simultaneous equation method (SEM), absorbance ratio method (ARM) and 1st derivative (zero-crossing) spectroscopic approach (FDR), were created and authenticated by validation for synchronized estimation of ALI and AMLO in tablet formulation. Materials and Methods: The SEM was used to measure the absorbance of both medicines at 237 and 280 nm. ALI and AMLO were calculated using 237 and 271 nm, respectively, in the ARM. ALI and AMLO, on the other hand, used the FDR technique to transform UV spectra to first derivative spectra, with the first derivative signal captured at 237 and 254 nm, respectively. The wavelength interval (Δλ) was kept at 2 and the scaling factor was kept at 1 when transforming zero-order spectra using the first derivative approach. Validation of the proposed processes was done in compliance with the “International Conference on Harmonization” (ICH) recommendations. Results: SEM and ARM both showed a linear outcome in the range of 1-50 µg/ml for ALI and AMLO. FDR, on the other hand, was shown to be more sensitive and linear between 0.5 and 50 µg/ml for both medications. The results of the method validation parameters were within the allowed ranges of the ICH guidelines. Conclusion: The proposed procedures were shown to be relatively quick, sensitive, simple, and cost-effective, and can thus be used for scheduled quality control analysis of ALI and AMLO in the mixed tablet.

Cardio-oncology: Capecitabine Can Sometimes be Heatbreaking Capecitabine-Induced Takotsubo Cardiomyopathy Case Report and Literature Review

Capecitabine has been more recognized for its cardiotoxicity with an incidence that varies widely. It demonstrates its toxicity in the forms of acute coronary syndrome, arrhythmias and, to a lesser extent, cardiomyopathy. There are several proposed theories including coronary vasospasm, endothelial injury, and oxidative stress. We present a case of capecitabine-induced cardiomyopathy in a patient with pancreatic cancer and mild coronary artery disease, and shed light on other cardio-toxic agents, their proposed mechanism of cardiotoxicity, and on cardiomyopathy in general.

A Novel Approach to the Treatment of Pembrolizumab-induced Psoriasis Exacerbation: A Case Report

While immune checkpoint inhibitors have been groundbreaking for cancer treatment, there are many reported cases of patients undergoing immunotherapy who have discontinued or temporarily interrupted treatment due to the development of autoimmune-related adverse effects. Here, we present a 63-year-old female with a history of psoriasis (in spontaneous remission) and newly diagnosed poorly differentiated lung adenocarcinoma (pTXN3M1a) who experienced a severe flare-up of her psoriasis three months after initiating single-agent pembrolizumab. The patient was initially treated with topical clobetasol propionate ointment, however, due to minimal response to this regimen, the patient was commenced on secukinumab; an IL-17 inhibitor. To our knowledge, this is the first case of the successful use of secukinumab for the treatment of immunotherapy-induced psoriasis. More importantly, immunotherapy with pembrolizumab was continued successfully with the co-administration of secukinumab without complications or the recurrence of non-small cell lung cancer (NSCLC).

Effect of Vaccinium macrocarpon on MK-801-induced psychosis in mice

OBJECTIVES

This study was aimed to investigate the effect of aqueous cranberry extract (ACE) on MK-801-induced psychosis in mice.

MATERIALS AND METHODS

MK-801-treated mice were administered ACE (1 and 2 g/kg, p.o.) for 14 days. Various behavioral parameters and neurochemical estimations such as dopamine (DA), 5-hydroxytryptamine (5-HT), norepinephrine (NE), gamma-aminobutyric acid (GABA), glutamate, and glycine as well as markers of oxidative stress such as nitrite levels were measured.

RESULTS

Psychosis-induced mice showed a significant elevation of immobility time in forced swim test, locomotor activity, and reduction in time of permanency in rota-rod test, escape latency time in Cook's pole test while treatment with ACE showed a significant alteration in above-mentioned behavioral parameters in MK-801-induced psychosis. Moreover, MK-801-induced psychosis in the mice showed a significant increase in DA, 5-HT, and NA levels and decrease in GABA, glutamate, and glycine levels in the brain. In contrast, treatment with ACE at both doses remarkably altered the neurochemical parameters. In addition, ACE-treated mice showed a substantial reduction in acetylcholinesterase, D-amino acid oxidase enzyme activity, and nitrite levels which were elevated by the administration of MK-801.

CONCLUSIONS

Treatment with ACE once for 14 days (1 and 2 g/kg) significantly ameliorated the behavioral symptoms in experimentally induced psychosis by virtue of neuromodulation and decreased oxidative stress.

Anti-anaphylactic and antiasthmatic activity of Euphorbia thymifolia L. on experimental animals

In Ayurveda, Euphorbia thymifolia L. (Euphorbiaceae) prescribed in the treatment of various ailments like bronchial asthma, cough, diarrhea and bleeding piles. The present study was investigated to evaluate antianaphylactic, mast cell stabilizing and antiasthmatic activity of methanol and aqueous extract of E. thymifolia (ET) on experimental animals. Anaphylaxis was induced by administration of horse serum and triple antigen vaccine intraperitoneal (i.p.) in albino Wistar rats. Extracts of ET were administered to the rats in dose of 250 and 500 mg/kg orally for 14 days. At the end of treatment, asthma score was measured and various blood parameters like differential count (DC), total WBC count and IgE were estimated. Interleukin (IL)-4, IL-5 and TNF-α were measured by ELISA commercial kit from BALF. Histopathological changes of lungs were observed. Antiasthmatic activity of extracts of ET was also studied on histamine-induced bronchospasm in guinea pigs. In vitro mast cell stabilizing activity of extracts was evaluated on compound 48/80 challenged rat intestinal mesenteric mast cells. The treatment with extracts of ET produced significant decrease in asthma score and they also brought to normalcy the increased total WBC, DC counts, serum IgE, TNF-α, IL-4 and IL-5 in BALF. The histopathological study further supported the protective effect of ET extracts. The pretreatment with extracts of ET displayed significant reduction in degranulation of mesenteric mast cell numbers. The treatment with extracts of ET significantly increased in time of PCD. Thus, these findings concluded that E. thymifolia could be effectively used in the treatment of anaphylaxis and asthma.

Antiurolithiatic effect of lithocare against ethylene glycol-induced urolithiasis in Wistar rats

Aim:

This study is aimed to investigate the protective effect of Lithocare (LC) (a polyherbal formulation) against ethylene glycol (EG) induced urolithiasis in Wistar rats.

Materials and Methods:

The protective effect of LC (400 and 800 mg/kg) was evaluated using EG-induced urolithiasis in rats.

Results:

Administration of EG in drinking water resulted in hyperoxaluria, hypocalcemia as well as an increased renal excretion of phosphate. Supplementation with LC significantly reduced the urinary calcium, oxalate, and phosphate excretion dose-dependently. There was a significant reduction in the levels of calcium, oxalate as well as a number of calcium oxalate crystals deposits in the kidney tissue of rats administered with LC in EG-treated rats. There was a significant reduction in creatinine, urea, uric acid, and blood urea nitrogen when LC was administered in EG-treated rats.

Conclusions:

From this study, it was concluded that the supplementation of LC protected EG-induced urolithiasis as it reduced the growth of urinary stones. The mechanism underlying this effect might be due to its antioxidant, diuretic, and reduction in stone-forming constituents.

Maxcal-C (a polyherbal formulation) prevents ovariectomy-induced osteoporosis in rats

Objectives:

The aim of the present study was to investigate the anti-osteoporotic activity of Maxcal-C in ovariectomy (OVX)-induced osteoporosis in rats.

Materials and Methods:

Sham-operated control rats were designated as Group I; Group II animals served as OVX control; Group III OVX control rats treated with Calcium Sandoz (50 mg/kg, p.o.); Group IV and V OVX control rats treated with Maxcal-C (250 and 500 mg/kg, p.o.), respectively. All the aforementioned treatments were given for four weeks after the development of osteoporosis. At the end of the treatment, serum biochemical parameters such as serum calcium and alkaline phosphate were measured. After sacrificing the animals, femoral bone parameters with histology, body weight, and bone breaking strength of 5^th lumbar vertebra were measured.

Results:

The treatment with Maxcal-C showed a significant improvement in serum biochemical, femoral bone parameters, and bone breaking strength of 5^th lumbar vertebra with histopathological changes.

Conclusion:

The finding of the present study indicates that Maxcal-C showed a potential anti-osteoporotic activity. These results support the traditional use of Maxcal-C in the treatment of osteoporosis.

Nanostructured lipid carriers for oral bioavailability enhancement of raloxifene: Design and in vivo study

The objective of present work was to utilize potential of nanostructured lipid carriers (NLCs) for improvement in oral bioavailability of raloxifene hydrochloride (RLX). RLX loaded NLCs were prepared by solvent diffusion method using glyceryl monostearate and Capmul MCM C8 as solid lipid and liquid lipid, respectively. A full 3(2) factorial design was utilized to study the effect of two independent parameters namely solid lipid to liquid lipid ratio and concentration of stabilizer on the entrapment efficiency of prepared NLCs. The statistical evaluation confirmed pronounced improvement in entrapment efficiency when liquid lipid content in the formulation increased from 5% w/w to 15% w/w. Solid-state characterization studies (DSC and XRD) in optimized formulation NLC-8 revealed transformation of RLX from crystalline to amorphous form. Optimized formulation showed 32.50 ± 5.12 nm average particle size and -12.8 ± 3.2 mV zeta potential that impart good stability of NLCs dispersion. In vitro release study showed burst release for initial 8 h followed by sustained release up to 36 h. TEM study confirmed smooth surface discrete spherical nano sized particles. To draw final conclusion, in vivo pharmacokinetic study was carried out that showed 3.75-fold enhancements in bioavailability with optimized NLCs formulation than plain drug suspension. These results showed potential of NLCs for significant improvement in oral bioavailability of poorly soluble RLX.

Protective effect of simvastatin and rosuvastatin on trinitrobenzene sulfonic acid-induced colitis in rats

Objective:

Statins have anti-inflammatory effects that are not directly related to their cholesterol lowering activity. This study was carried out to evaluate the effect of simvastatin or rosuvastatin on the extent of colonic mucosal damage and on the inflammatory response in trinitrobenzene sulfonic acid (TNBS)-induced ulcerative colitis.

Materials and Methods:

Ulcerative colitis was induced by single intrarectal injection of 120 mg/kg TNBS. Test groups were treated with simvastatin (10 mg/kg, p.o.) or rosuvastatin (10 mg/kg, p.o.). Colonic mucosal inflammation was evaluated clinically, biochemically, and histologically.

Result:

Disease activity index score in TNBS-treated rats, as determined by weight loss, stool consistency, fecal occult blood, were significantly lowers in simvastatin or rosuvastatin-treated rats than TNBS-treated animals. Simvastatin or rosuvastatin counteracted the reduction in colon length, decreased colon weight, neutrophil accumulation, and tumor necrosis factor-alpha level in TNBS-induced colitis. Simvastatin and rosuvastatin also inhibited the increase in oxidative stress levels after TNBS administration.

Conclusions:

These results suggest that simvastatin and rosuvastatin significantly ameliorate experimental colitis in rats, and these effects could be explained by their anti-inflammatory and antioxidant activity.

Effect of coenzyme Q10 alone and its combination with metformin on streptozotocin-nicotinamide-induced diabetic nephropathy in rats

Objectives:

This study was aimed to investigate the therapeutic potential of coenzyme Q10 and its combination with metformin on streptozotocin (STZ)-nicotinamide-induced diabetic nephropathy (DN).

Materials and Methods:

Type 2 diabetes in rats was induced with STZ-nicotinamide. The diabetic rats were treated with coenzyme Q10 (10 mg/kg, p.o.) alone or coenzyme Q10 + metformin. Various parameters of renal function tests such as serum creatinine, urea, uric acid, and markers of oxidative stress such as renal malondialdehyde (MDA) level, superoxide dismutase (SOD), and catalase (CAT) activities were measured. Tumor necrosis factor-α (TNF-α), myeloperoxidase (MPO) activity, transforming growth factor-β (TGF-β), and nitrite content were estimated in renal tissues. All treated animal were subjected to histopathological changes of kidney.

Result:

Diabetic rats showed a significant reduction in renal function, which was reflected with an increase in serum urea, serum creatinine, uric acid. In addition, STZ-nicotinamide caused renal tubular damage with a higher MDA level, depletion of SOD and CAT activity and glutathione (GSH) level. Moreover, TNF-α, MPO activity, TGF-β, and nitrite content were significantly increased in diabetic rats, while treatment with coenzyme Q10 or metformin or their combination ameliorate STZ-nicotinamide induced renal damage due to improvement in renal function, oxidative stress, suppression of TNF-α, MPO activity, TGF-β and nitrite content along with histopathological changes.

Conclusions:

This finding suggests that the treatment with coenzyme Q10 or metformin showed significant renoprotective effect against STZ-nicotinamide-induced DN. However, concomitant administration of both showed a better renoprotective effect than coenzyme Q10 or metformin alone treatment.

Amelioration of cisplatin-induced nephrotoxicity by statins

Objectives:

This study aimed to investigate the protective effect of simvastatin (SIM) and rosuvastatin (RST) on cisplatin (CIS)-induced nephrotoxicity.

Materials and Methods:

Adult female Wistar rats were divided into six groups: Control group (Group 1) received 0.5% sodium carboxy methyl cellulose, group 2 and group 3 received SIM and RST for 10 days, respectively, and group 4 was injected single dose of CIS (7 mg/kg, i.p.). Group 5 and 6 were treated with SIM (10 mg/kg, p.o.) and RST (10 mg/kg, p.o.) for 10 days, respectively. All groups received cisplatin on the 5^th day of treatment. Renal function tests like serum creatinine, urea, BUN, albumin, calcium, uric acid and magnesium, serum lipids, and markers of oxidative stress such as renal malondialdehyde (MDA) level and superoxide dismutase (SOD) and catalase (CAT) activities were measured. All tissues were investigated for histopathological changes.

Result:

CIS reduced the renal function, which was reflected with significant increase in serum urea, BUN, serum creatinine, uric acid and also significant decrease serum calcium, magnesium, albumin levels. In addition, cisplatin caused renal tubular damage with a higher MDA level, depletion of SOD and CAT activity, and elevation of serum lipids. SIM or RST ameliorate CIS induced renal damage due to improvement in renal function, oxidative stress, suppression of serum lipids, and histological alteration.

Conclusions:

This finding suggests that simvastatin and rosuvastatin may have a protective effect against cisplatin-induced kidney damage via amelioration of lipid peroxidation as well as due to improvement of renal function, and lipid-lowering effects.

Cardioprotective Effects of Lagenaria siceraria Fruit Juice on Isoproterenol-induced Myocardial Infarction in Wistar Rats: A Biochemical and Histoarchitecture Study

The present study was designed to evaluate the cardioprotective effects of Lagenaria siceraria fruit juice in isoproterenol-induced myocardial infarction. Rats injected with isoproterenol (200 mg/kg, s.c.) showed a significant increase in the levels of serum uric acid, tissue Na⁺⁺ and Ca⁺⁺ ions and membrane-bound Ca⁺²-ATPase activity. A significant decrease in the levels of serum protein, tissue K⁺ ion, vitamin E level, and the activities of Na⁺/K⁺-ATPase and mg⁺²-ATPase was observed. Isoproterenol injected rats also showed a significant increase in the intensity of lactate dehydrogenase isoenzyme and histopathologic alterations in the heart. Treatment with L. siceraria fruit juice (400 mg/kg/day, p.o.) for 30 days and administration of isoproterenol on 29^th and 30^th days showed a protective effect on altered biochemical and histopathologic changes. These findings indicate the cardioprotective effect of L. siceraria fruit juice in isoproterenol-induced myocardial infarction in rats.

PA01.46. Gastro protective effect of normacid powder, an herbal formulation on experimental induced ulcer in mices

Purpose:

Present study was carried out to investigate antiulcer activity of Normacid powder in diclofenac and pylorus ligated induced ulceration in the albino mices.

Method:

Preliminary normacid powder was subjected to the acute oral toxicity study according to the OECD guideline no. 425. Based on which, two dose levels i.e. 250 and 500 mg/kg were selected for the further study. Various parameters were studied viz. gastric juice volume, pH, total acidity, free acidity, ulcer index, percentage inhibition, anti oxidants parameter, mucin level and mucosal nitrate level of ulceration was determined for diclofenac and pylorus induced ulcer model. Ranitidine at 20 mg/kg was used as the standard drug.

Result:

Pre-treatment of normacid powder showed significant (P<0.001) decrease in the gastric volume, total acidity and free acidity. However, pH of the gastric juice was significantly (P<0.001) increased only at higher dose, 500 mg/kg. It showed also significant (P<0.001) decrease in number of ulcers and ulcer score index in diclofenac and pylorus ligation induced ulceration models. The increase in the level of superoxide dismutase, catalase, reduced glutathione and decrease in lipid peroxidation in both the models showed the antioxidant activity of the formulation. Also increase in mucin and mucosal nitrate level in both models showed the cytoprotective activity of the formulation. Normacid powder possesses significant antiulcer properties in a dose dependent manner.

Conclusion:

In conclusion the antiulcer properties of the normacid powder may be due to the modulation of defensive factors, improvement in gastric cytoprotection and due to antioxidant property.

Effects of Lagenaria sicessaria fruit juice on lipid profile and glycoprotein contents in cardiotoxicity induced by isoproterenol in rats

This study investigated antihyperlipidemic effects of Lagenaria siceraria fruit juice (LSFJ) in isoproterenol (ISO)induced cardiotoxicity in rats. Rats treated with ISO (200 mg/kg, s.c.) showed a significant increase in the levels of triglycerides, cholesterol, and free fatty acids, in both serum and heart tissue. An increase in the levels of phospholipids, low-density lipoprotein, and very low-density lipoprotein-cholesterol, and decrease in high-density lipoprotein-cholesterol in serum and phospholipid levels in the heart were observed. ISO intoxicated rats also showed a significant decrease in the activities of lecithin: cholesterol acyl transferase, whereas lipoprotein lipase was found to be increased. Administration of LSFJ (400 mg/kg, p.o.) for 30 consecutive days and challenged with ISO on day 29th and 30th significantly attenuated these alterations and restored the levels of serum and heart lipids along with lipid metabolizing enzymes. Histopathological observations were also in correlation with the biochemical parameters. These findings indicate the protective effect of LSFJ during ISO-induced cardiotoxicity in rats.

Tomato lycopene attenuates myocardial infarction induced by isoproterenol: electrocardiographic, biochemical and anti-apoptotic study

OBJECTIVE

To assess the protective effects of lycopene on electrocardiographic, hemodynamic, biochemical and apoptotic changes in isoproterenol induced myocardial infarction.

METHODS

Myocardial infarction was induced in rats by subcutaneous injection of isoproterenol (200 mg/kg) for two consecutive days at an interval of 24 h. Rats were treated with lycopene (10 mg/kg/day, p.o.) for a period of 30 days and isoproterenol (ISO) was injected on the 29th and 30th day. At the end of experiment i.e. on the 31st day electrocardiographic, hemodynamic, biochemical and apoptotic changes were monitored from control and experimental groups.

RESULTS

ISO injected rats showed a significant alteration in electrocardiograph pattern and hemodynamic changes (i.e. systolic, diastolic and mean arterial pressure). It also showed significant increase in C-reactive protein, myeloperoxidase, nitrite levels and Caspase-3 protease activity. In addition, it also exhibited alteration in the levels of electrolytes (Na(+), K(+) and Ca(2+)), vitamin E, uric acid and serum protein. Gel electrophoresis of ISO injected rats showed increase in DNA fragmentation. Triphenyl tetrazolium chloride staining of the heart section shows increase area of infarction in ISO injected rats. Pre-co-treatment with lycopene significantly prevented the ISO induced alteration in ECG, haemodynamic, biochemical and apoptotic changes.

CONCLUSIONS

The present result shows that treatment of lycopene in ISO injected rats significantly attenuates induced myocardial infarction.

Retinol-binding protein 4 : a possible role in cardiovascular complications

BACKGROUND AND PURPOSE

Retinol-binding protein 4 (RBP4) is an adipocyte-secreted hormone proposed to link obesity with insulin resistance. However, the role of RBP4 in cardiovascular complications is yet to be fully understood. The present study is aimed to decipher the association between RBP4 with pro-inflammatory cytokines and low-density lipoprotein (LDL) cholesterol in diet-induced obese and hyperlipidaemic mice. To understand the correlation, rimonabant, an anti-obesity drug, has been used to relieve the atherosclerotic predisposition.

EXPERIMENTAL APPROACH

Adipose and/or aortic tissue expressions of RBP4, pro-inflammatory cytokine genes and circulating LDL levels were measured in high fat (HF)-fed female C57BL/6 and high cholesterol (HC)-fed apolipoprotein E3 (ApoE3) Leiden mice.

KEY RESULTS

Mice fed a HF diet had a significantly increased adipose expression of RBP4, TNF-α and monocyte chemoattractant protein 1 (MCP-1) and down-regulated adiponectin mRNA levels. A significant increase in aortic RBP4 and MCP-1 expression and circulating levels of LDL and C-reactive protein (CRP) was found in the ApoE3 mice fed a HC diet. Interestingly, rimonabant treatment lowered the elevated aortic RBP4, MCP-1 expressions and significantly reduced the serum levels of LDL, CRP, RBP4 and MCP-1.

CONCLUSION AND IMPLICATIONS

Our results indicate that RBP4 is positively associated with markers of inflammation in obese and pro-atherogenic conditions and could play a role in a predisposition to atherosclerosis. Furthermore, our results indicate that rimonabant may improve vascular function by modulating RBP4 along with pro-inflammatory cytokines.

Effect of vitamin E alone and in combination with lycopene on biochemical and histopathological alterations in isoproterenol-induced myocardial infarction in rats

Background:

The present study has been designed to evaluate the combined cardioprotective effect of vitamin E and lycopene on biochemical and histopathological alteration in isoproterenol-induced myocardial infarction in rats.

Materials and Methods:

Adult male albino rats of Wistar strain were treated with isoproterenol (200 mg/kg, s.c.) for 2 days at an interval of 24 h to develop myocardial infarction. Vitamin E (100 mg/kg/day, p.o.) and lycopene (10 mg/kg/day, p.o.) were administered alone and in combination for 30 days. Change in body weight and organ weight were monitored. Levels of serum marker enzymes (AST, ALT, LDH and CK-MB), lipid peroxidation, endogenous antioxidants (GSH, GPX, GST, SOD and CAT), membrane bound enzymes (Na⁺/K⁺ ATPases, Mg²⁺ ATPases and Ca²⁺ ATPases) were evaluated. LDH isoenzyme separation was carried out using gel electrophoresis. Histopathology of heart tissue was performed.

Results:

Induction of rats with isoproterenol resulted in a significant elevation in organ weight, lipid peroxidation, serum marker enzymes (AST, ALT, CK-MB and LDH), and Ca ²⁺ ATPases, whereas it caused a significant (P < 0.001) decrease in body weight, activities of endogenous antioxidants (GSH, GP_x, GST, SOD and CAT), Na⁺/K⁺ and Mg²⁺ ATPases. ISO treated rats showed high intensity band of LDH1-LDH2 isoenzymes. Treatment with the combination of Vitamin E and lycopene for 30 days significantly attenuated these changes as compared to the individual treatment and ISO treated groups. Histopathological observations were also in correlation with the biochemical parameters.

Conclusion:

These findings indicate the synergistic cardioprotective effects of vitamin E and lycopene during ISO-induced myocardial infarction in rats.

Adipocytokines: The pied pipers

Even though there have been major advances in therapy, atherosclerosis and coronary artery disease retain their lead as one of the major causes of morbidity and mortality in the first decade of 21(st) century. To add to the woes, we have diabetes, obesity and insulin resistance as the other causes. The adipose tissue secretes several bioactive mediators that influence inflammation, insulin resistance, diabetes, atherosclerosis and several other pathologic states besides the regulation of body weight. These mediators are mostly proteins and are termed "adipocytokines". Adiponectin, resistin, visfatin, retinol binding protein-4 (RBP-4) and leptin are a few such proteins. Adiponectin is a multimeric protein, acting via its identified receptors, AdipoR1 and AdipoR2. It is a potential biomarker for metabolic syndrome and has several antiinflammatory actions. Adiponectin increases insulin sensitivity and ameliorates obesity. Resistin, another protein secreted by the adipose tissue, derived its name due to its involvement in the development of insulin resistance. It plays a role in the pathophysiology of several conditions because of its robust proinflammatory activity mediated through the activation of extracellular signal regulated kinases 1 and 2 (ERK 1/2). In 2007, resistin was reported to have protective effect in ischemia-reperfusion injury and myocyte-apoptosis in the setting of myocardial infarction (MI). RBP-4 is involved in the developmental pathology of type 2 diabetes mellitus and obesity. Visfatin has been described as an inflammatory cytokine. Increased expression of visfatin mRNA has been observed in inflammatory conditions like atherosclerosis and inflammatory bowel disease. Leptin mainly regulates the food intake and energy homeostasis. Leptin resistance has been associated with development of obesity and insulin resistance. Few drugs (thiazolidinediones, rimonabant, statins, etc.) and some lifestyle modifications have been found to improve the levels of adipocytokines. Their role in therapy has a lot in store to be explored upon.

Effect of green tea extract on Doxorubicin induced cardiovascular abnormalities: antioxidant action

Doxorubicin (DOX) induces oxidative stress leading to cardiovascular abnormalities. Green tea extract (GTE) is reported to possess antioxidant activity mainly by means of its polyphenolic constituent, catechins. Our study was aimed to find out the effect of GTE (100 mg/kg / day p.o. for 28 days) on DOX induced (3 mg/kg, IP on days 1, 7, 14, 21, 28) cardiovascular abnormalities in rat heart. DOX treatment led to significant increase in blood pressure, ST interval, serum levels of LDH, CK, SGOT, lipid peroxidation .The antioxidant enzymes such as super oxide dismutase, catalase and reduced-glutathione were decreased considerably in the heart of DOX treated rats as compared to the normal control. A combined treatment with GTE and DOX showed a considerable decrease in serum markers of cardiotoxicity such as LDH, CK, SGOT and lipid peroxides. There was significant increase in the activities of antioxidant enzymes and also showed improvement in hemodynamic parameters and ECG changes as compared to DOX treated animals. DOX treatment caused disorganization of myocardial tissue which was restored in animals treated with GTE along with DOX. Thus it can be concluded that GTE possesses an antioxidant activity and by virtue of this action it can protect the heart from DOX induced cardiovascular abnormalities.

Effect of Hemidesmus indicus on ischemia-reperfusion injury in the isolated rat heart

The root extract of Hemidesmus indicus (Linn.) R. Br. (Asclepiadaceae) (HI) was studied for its cardioprotective effect in Langendorff-perfused rat hearts. HI was perfused for 15 min at a concentration of 0.09 g/L prior to 30 min global ischemia/120 min reperfusion (I/R). Recovery of functional parameters, reperfusion arrhythmias, and infarct size (TTC staining) served as the end-points. After 15 min of perfusion with HI, the left ventricular developed pressure (LVdevP) and HR (heart rate) were not altered significantly (p>0.05), as compared with the pre-drug values. During R, HI showed a significantly higher (p<0.05) recovery of LVdevP at nearly all time points. The recovery of maximal rate of pressure development (+dP/dtmax) and left ventricular end-diastolic pressure (LVEDP) at 40 min of R were significantly better than in non-treated controls. There was also a significant reduction in the total number of ventricular premature beats (VPB) and duration of ventricular tachycardia (VT). HI can protect ischemic myocardium against contractile dysfunction and reperfusion-induced arrhythmias and reduce the extent of irreversible tissue damage following I/R in rat hearts.

Selective β1-adrenoreceptor blocking activity of newly synthesized acyl amino-substituted aryloxypropanolamine derivatives, DPJ 955 and DPJ 890, in rats

The in-vivo β-adrenoreceptor antagonistic activity of test compounds DPJ 955 and DPJ 890 was assessed against β-adrenoreceptor agonist (isoprenaline) induced tachycardia in anaesthetized rats. The selectivity to block isoprenaline responses on different β-adrenoreceptor subtypes (β1, β2 and β3) of the test compounds was carried out on isolated rat right atria, isolated rat uterus and isolated rat colon preparations, respectively. Intravenous injection of isoprenaline alone in anaesthetized rats caused hypotension and tachycardia. DPJ 955 or DPJ 890 alone produced a fall in mean arterial pressure and bradycardia in a dose-dependent manner. Administration of isoprenaline to anaesthetized rats pre-treated with test compounds significantly blocked both the tachycardial and hypotensive responses induced by isoprenaline. The test compounds shifted the concentration response curves of isoprenaline towards the right for isolated rat right atrial preparations, rat uterus and rat colon, indicating β1, β2 and β3 adrenoreceptor blockade, respectively. The selectivity ratio for β1/β-adrenoreceptors to DPJ 955 and DPJ 890 was 64.6 and 83.2, respectively. DPJ 890 was more potent in blocking β1-adrenoreceptors and was more selective towards β1 receptors than to other β-adrenoreceptor subtypes. In conclusion, DPJ 955 and DPJ890 have β-adrenoreceptor blocking activity with high selectivity for the β1-adrenoreceptor subtype.

Subtherapeutic dose of pioglitazone reduces expression of inflammatory adipokines in db/db mice

Agonists of the thiazolidinedione class of peroxisome proliferator-activated receptor-gamma exhibit both insulin-sensitizing and anti-inflammatory effects. We hypothesized that pioglitazone might be able to exert its anti-inflammatory properties at a lower dose than that required for its insulin-sensitizing effect. In order to investigate this hypothesis, we evaluated the effects of pioglitazone on inflammatory as well as metabolic biomarkers in serum and white adipose tissue (WAT) at 2 different doses. Female db/db mice were treated orally with therapeutic (30 mg/kg) and subtherapeutic (3 mg/kg) doses of pioglitazone for 14 days followed by an oral glucose tolerance test. Other parameters measured were inflammatory markers such as tumor necrosis factor (TNF)-alpha, interleukin-6 (IL-6) and metabolic biomarkers in serum (insulin, glucose and adiponectin). Moreover, adiponectin, fatty acid-binding protein (aP2) and lipoprotein lipase (LPL) mRNA expression in WAT were determined by real-time PCR. A subtherapeutic dose of pioglitazone significantly suppresses the expression of TNF-alpha and IL-6 mRNA in WAT, but does not alter the serum glucose, insulin and WAT expression of adiponectin, adipocyte aP2 and LPL. A therapeutic dose of pioglitazone improves insulin sensitivity, enhances LPL, aP2 and adiponectin expression, and also suppresses TNF-alpha and IL-6 expression. In conclusion, the current study indicates that the anti-inflammatory effect of pioglitazone is produced at a subtherapeutic dose, which is considerably lower than the dose needed to produce any desired metabolic effects. Anti-inflammatory effects of pioglitazone may precede its insulin-sensitizing effects in db/db mice.

Protection against in vivo focal myocardial ischemia/reperfusion injury-induced arrhythmias and apoptosis by hesperidin

Among the heart diseases, ischemia and reperfusion (I/R) induced arrhythmias contribute to episodes of sudden death. Cardiac arrhythmias during ischemia reperfusion are believed to be related to oxidative stress. Therefore, the aim of this study was to examine whether treatment with hesperidin alleviates arrhythmias and infarct size in experimentally-induced myocardial I/R injury using an in vivo rat model. In this study haemodynamics parameters, markers of inflammation, biomarkers of oxidative stress and tissue nitrite level and infarct size of the heart were estimated in various groups. I/R showed a significant decrease in tissue nitrite and antioxidant level and significant increase in arrhythmias, inflammation and myocardial cell apoptosis. Treatment with hesperidin showed a significant increase in tissue nitrite, antioxidant level and reduction in inflammation, arrhythmias and apoptosis. In conclusion, the protecting effect of hesperidin in I/R induced arrhythmias is due to reduction in inflammation and oxidative stress.

Nebivolol reduces experimentally induced warm renal ischemia reperfusion injury in rats

Ischemia/reperfusion injury, which is commonly seen in the field of renal surgery or transplantation, is a major cause of acute renal failure. The objective of the present study was to examine the role of nebivolol in modulating peroxynitrite species-induced inflammation and apoptosis after renal warm ischemia/reperfusion injury in rats. The present study was designed to investigate the effects of nebivolol on the renal warm ischemia/reperfusion injury in rats treated with the nitric oxide synthase inhibitor, N(omega)-nitro-L-arginine methyl ester. After right nephrectomy, nebivolol was administered for 15 days. On the 16(th) day, ischemia was induced in contra lateral kidney for 45 min, followed by reperfusion for 24 hr. Renal function, inflammation, and apoptosis were estimated at the end of 24 hr reperfusion. Nebivolol improved the renal dysfunction and reduced inflammation and apoptosis after renal ischemia/reperfusion injury. In conclusion, nebivolol shows potent anti-apoptotic and anti-inflammatory properties due to its NO-releasing property. These findings may have major implications in the treatment of human ischemic acute renal failure.

Synthesis, antileukemic and antiplatelet activities of 2,3-diaryl-6,7-dihydro-5H-1,4-diazepines

The synthesis, antileukemic and antiplatelet activity evaluation of 2,3-diaryl-6,7-dihydro-5H-1,4-diazepines are described. In general, it was found that compound 17o showed moderate antileukemic activity against MOLT3 human leukemic cancer cell lines. An arachidonic acid induced platelet aggregation effect on washed rat platelets was studied. Compound 17i was found to be the most potent. The antiplatelet properties may be mediated by interference with the arachidonic acid pathway.

Gender specific effect of progesterone on myocardial ischemia/reperfusion injury in rats

The study was designed to investigate the effect of progesterone and its gender based variation on myocardial ischemia/reperfusion (I/R) injury in rats. Adult Sprague Dawley rats were divided into vehicle treated reperfusion injury group male (I/R-M), female (I/R-F), ovariectomised (I/R-OVR) and progesterone treatment (I/R-M+PG, I/R-F+PG, I/R-OVR+PG) groups, respectively. I/R injury was produced by occluding the left descending coronary artery (LCA) for 1 h and followed by re-opening for 1 h. Progesterone (2 mg kg(-1) i.p.) was administered 30 min after induction of ischemia. Hemodynamic parameters (+/-dp/dt, MAP), heart rate, ST-segment elevation and occurrence of ventricular tachycardia (VT) were measured during the I/R period. The myocardial infarct area, oxidative stress markers, activities of myeloperoxidase (MPO) and creatine kinase (CK) were determined after the experiment along with the assessment of the effect on apoptotic activity by using DNA fragmentation analysis. Histological observations were carried out on heart tissue. Treatment with progesterone significantly (P<0.05) reduced infarct area, lipid peroxidation (LPO) level and activity of MPO in females (I/R-F+PG) as compared to ischemic females (I/R-F). Progesterone significantly (P<0.001, P<0.05) inhibited serum CK activity and incidences of VT in female rats. Superoxide dismutase (SOD) activity, reduced glutathione (GSH) levels were significantly elevated (P<0.05) in I/R-F+PG group. Internucleosomal DNA fragmentation was less in I/R-F+PG group when compared to I/R-F group. The ischemic male and ovariectomised (I/R-M and I/R-OVR) counterparts did not show any significant change after progesterone treatment. In conclusion, the cardioprotective effect of progesterone on myocardial I/R injury induced damage is based on gender of the animal. The protective effect could be mediated by attenuation of inflammation and its possible interaction with endogenous estrogen.

Synthesis of new chemical entities from paracetamol and NSAIDs with improved pharmacodynamic profile

It was envisaged to combine high antipyretic activity of paracetamol into commonly used NSAIDs. To achieve this goal new chemical entities were synthesized by chemically combining paracetamol and NSAIDs, and biologically evaluated for their antipyretic, analgesic, anti-inflammatory and ulcerogenic potential. The acid chloride of parent NSAIDs was reacted with excess of p-aminophenol to yield the desired p-amidophenol derivatives (1B-7B). Acetate derivatives (1C-7C) of these phenols (1B-7B) were also prepared by their treatment with acetic anhydride, in order to see the impact of blocking the free phenolic group on the biological activity of the derivatives. All the synthesized p-amidophenol derivatives showed improved antipyretic activity than paracetamol with retention of anti-inflammatory activity of their parent NSAIDs. These compounds elicited no ulcerogenicity unlike their parent drugs.

Effect of Atorvastatin Treatment on Isoproterenol-Induced Myocardial Infarction in Rats

In the present study, chronic treatment of atorvastatin was evaluated on isoproterenol-induced myocardial infarction. Male Sprague-Dawley rats (200 +/- 25 g) were randomized into the following four groups: (1) control group, (2) isoproterenol-treated group, (3) atorvastatin-treated group, and (4) isoproterenol- and atorvastatin-treated group. Various serum and tissue parameters as well as histopathological studies were carried out in all groups. Isoproterenol administration produced severe myocardial damage and oxidative stress in rats. Atorvastatin treatment reduced myocardial infarction which has been reflected by improvement in serum parameters, ATPase activities and histopathological lesions. However, it could not reduce oxidative stress and hypertrophy induced by isoproterenol. Hence, it can be concluded that atorvastatin may protect myocardial infarction induced by isoproterenol independent of its antioxidant properties.

Modification of biochemical parameters of gentamicin nephrotoxicity by coenzyme Q10 and green tea in rats

The present study was designed to investigate the possible potential protective role of coenzymeQ10 (CoQ10; 10 mg/kg/day, ip) and/or green tea (GT; 25mg/kg/day, po) against gentamicin (GM) nephrotoxicity. Marked increase in the level of serum urea. creatinine and lipid peroxidation (LPO) content was found after administration of gentamicin (80 mg/kg/day, ip) for eight days along with significant decrease in the antioxidant enzymes, superoxide dismutase (SOD), reduced glutathione (GSH), catalase (CAT) as well as brush border enzymes (Na+/K+ ATPase, Mg(+2)ATPase and Ca2+ ATPase). Treatment with CoQ10 or green tea alone with GM showed significant decrease in serum urea, creatinine and tissue LPO content and significant increase in antioxidant and membrane bound enzymes. Combined treatment with CoQ10 and green tea was more effective in mitigating adverse effect of GM nephrotoxicity. The present work indicated that CoQ10 and green tea due to their antioxidant activity modified the biochemical changes occurred during gentamicin nephrotoxicity and thus had a potential protective effect.