2', 4'-dihydroxy-3, 4-methylenedioxychalcone Activate Mitochondrial Apoptosis of Ehrlich Ascites Carcinoma Cells

Background:

Development of effective cancer-chemotherapy is the most challenging field due to the toxicity of chemo-agents.

Objective:

As chalcone has been known to have pharmacological applications, here the aim is to synthesized three chalcone derivatives, 2',4'-dihydroxy-3,4-methylenedioxychalcone (C1), 2'-hydroxy- 2,4, 6-trimethoxychalcone (C2) and 2'-hydroxy-4-methylchalcone (C3) and investigate their anti-cancer properties against Ehrlich Ascites Carcinoma (EAC) cell.

Method:

Anticancer properties against EAC cells were studied by examining growth inhibition, MTT assays, tumour-bearing mice survival, tumour weight measurement and haematological profiles. Moreover, apoptosis of EAC cells was investigated by fluorescence microscopy, flowcytometry and DNA fragmentation assays. Expression of apoptosis related genes were studied by reverse transcriptase-PCR (RT-PCR).

Results:

Among the compounds, C1 exhibited highest cell growth inhibition at 200 mg/kg/day (81.71%; P < 0.01). C1 treatment also increased the life span of EAC-bearing mice (82.60%, P < 0.05) with the reduction of tumour burden (<) compared to untreated EAC-bearing mice. In vitro study indicated that C1 killed EAC-cells in a dose-dependent manner and induced mitochondria-mediated apoptotic pathways. In addition, C1 treated cells exhibited increased apoptotic features such as membrane blebbing, chromatin condensation, and nuclear fragmentation after Hoechst 33342 staining. Increased fragmentation of DNA in gel electrophoresis followed by C1 treatment further confirmed apoptosis of EAC cells. EAC cells treated with C1 showed reduced Bcl-2 expression in contrast to notable upregulation of p53 and Bax expression. It implied that C1 could reinstate the expression of pro-apoptotic tumour suppressor and inhibit anti-apoptotic genes.

Conclusions:

Thus, C1 showed significant growth inhibitory properties and induced apoptosis of EAC cells.

Apoptotic and antioxidant activities of methanol extract of Mussaenda roxburghii leaves

roxburghii. Anticancer activity of MMR has been carried out on Ehrlich ascites carcinoma (EAC) cells with three different doses (20, 40 and 60 mg/kg/day) by observing different parameters such as tumor weight, survival time of EAC-bearing mice, growth inhibition of EAC cells, morphological changes and nuclear damage of EAC cells etc. whereas antioxidant activity was determined by measuring total antioxidant, DPPH free radical scavenging, ferrous reducing capacity assay. The extract showed highest anticancer activity at 60 mg/kg day¬-⁻¹(i.p.). It caused 81.4% (P<0.01) cells growth inhibition and reduced tumor burden significantly (78.5%; P<0.001) in comparison to control. It also increased life span of EAC-bearing mice significantly (73.5%; P<0.01). MMR treated EAC cells showed membrane blebbing, chromatin condensation, nuclear fragmentation (apoptotic feature) in Hoechst 33342 staining under fluorescence microscope. DNA fragmentation assay in agarose gel (1.5%) electrophoresis also rectified that it causes EAC cells death by apoptosis. MMR also exhibited moderate antioxidant properties in dose dependent manner. Thus, this plant can therefore be considering a resource for natural chemo-preventive drugs as well as a possible pharmaceutical supplement.

Pathogenesis of Cheyne-Stokes respiration in patients with congestive heart failure. Relationship to arterial PCO2

In order to determine which patients with congestive heart failure (CHF) develop Cheyne-Stokes respiration (CSR) during sleep, we compared the cardiorespiratory profiles of CHF patients with CSR to those of CHF patients without CSR. Overnight polysomnography and continuous transcutaneous PCO2 (tc PCO2) monitoring, estimation of left ventricular ejection fraction (LVEF), pulmonary function tests, and chest radiograph were performed on 16 consecutive patients with chronic, stable CHF. The tc PCO2 monitor (Kontron 7640) was calibrated so that measurements reflected arterial PCO2 values. A mean value was calculated for wakefulness (W) and total sleep time (TST). Circulation time (CT) from the lung to the carotid body was estimated from the end of an apnea or voluntary breath-hold to the nadir of oxygen desaturation recorded on an ear oximeter. The duration of CSR was expressed as a percent of TST. Nine patients developed CSR during sleep (52.5 +/- 31.6 percent TST) (group 1) and 7 did not (group 2). All patients were male and both groups were a similar age (64 +/- 8 vs 63 +/- 4 years) and weight (body mass index, 28.1 +/- 3.5 vs 25.4 +/- 3.4 kg/m2). There were no significant intergroup differences between LVEF (22 +/- 5.2 vs 24.1 +/- 5.2 percent), CT (19.1 +/- 3.6 vs 15.9 +/- 6.7 s), SaO2 (W) (94 +/- 1.2 vs 92.4 +/- 2.1 percent), and SaO2 (TST) (90.8 +/- 2.7 vs 92.4 +/- 2.1 percent). The tc PCO2 (W) was lower in group 1 (34.4 +/- 3.5 vs 38.1 +/- 1.9 mm Hg), increased during sleep by a similar amount in both groups (1.6 +/- 1.5 vs 2.1 +/- 2.2 mm Hg), and was significantly lower during sleep in group 1 (36.1 +/- 3.4 vs 40.2 +/- 2.2 mm Hg). We conclude that CHF patients with CSR hyperventilate during sleep and wakefulness and that CHF patients with awake hypocapnia are more likely to develop CSR during sleep. These findings indicate that arterial PCO2 is important in determining which CHF patients develop CSR.

ST-segment depression during sleep in obstructive sleep apnea

It was hypothesized that obstructive sleep apnea may precipitate myocardial ischemia, reflected by ST-segment depression, in some patients during sleep. Overnight sleep studies and simultaneous 3-channel Holter monitoring were performed on 23 consecutive patients with obstructive sleep apnea without a history of coronary artery disease. Each patient was randomly assigned to nasal continuous positive airway pressure for the first half of the night. An episode of significant ST depression was defined as > 1 mm from baseline for > 1 minute. The total duration (minutes) of ST depression was indexed to the total sleep time (minutes per hour of sleep). Seven patients (30%) had ST depression during sleep. In all 7 patients the duration of ST depression decreased during nasal continuous positive airway pressure (30 +/- 18 vs 11 +/- 13 minutes per hour of sleep) in association with a reduction in the apnea-hypopnea index (65 +/- 35 vs 7 +/- 6/hour), arousal index (49 +/- 14 vs 6 +/- 4/hour) and the duration that oxygen saturation was < 90% (44 +/- 27 vs 12 +/- 23% total sleep time). When patients were not on nasal continuous positive airway pressure, the apnea-hypopnea and arousal indexes were higher during periods of ST depression than when ST segments were isoelectric, whereas oxygen saturation was not different. These 7 patients underwent exercise testing, which was positive for inducible myocardial ischemia in 1 patient. It is concluded that ST depression is relatively common in patients with obstructive apnea during sleep and that the duration of ST depression is significantly reduced by nasal continuous positive airway pressure.(ABSTRACT TRUNCATED AT 250 WORDS)

Periodic leg movements during sleep before and after heart transplantation

We report the association between periodic leg movements (PLM) during sleep and congestive heart failure (CHF) in a patient who had a successful heart transplant. Pretransplant, the patient had chronic insomnia and CHF. Overnight polysomnography revealed severe PLM disorder and sleep disruption. Three months following transplantation his insomnia had resolved associated with a dramatic reduction in PLM.

Ventricular function in snorers and patients with obstructive sleep apnea

We hypothesized that intermittent hypoxemia and increased ventricular afterload due to obstructive apnea during sleep (OSA) would cause chronic left ventricular dysfunction. Overnight polysomnography, M-mode and two-dimensional echo-Doppler studies while awake were performed on 51 consecutive snorers, 30 with OSA and 21 without apnea. Patients with previous myocardial infarction, awake hypoxemia or hypercapnia, or other causes of nocturnal hypoxemia were excluded. Echo-Doppler measurements included end-diastolic right and left ventricular dimensions and wall thickness, indices of left ventricular systolic performance (fractional shortening, ejection fraction and ejection time and diastolic performance, (isovolumic relaxation time, ratio of peak early [E] to late [A] diastolic transmitral flow and mitral pressure half-time). Both OSA patients and nonapneic snorers were of similar age. Although OSA patients were heavier, had a greater apnea-hypopnea index, and significant nocturnal hypoxemia, their echo-Doppler measurements were within normal limits and were not significantly different from nonapneic snorers. It is concluded that isolated obstructive sleep apnea does not cause chronic left ventricular dysfunction.