Proto-oncogene cSrc-mediated RBM10 phosphorylation arbitrates anti-hypertrophy gene program in the heart and controls cardiac hypertrophy

AIMS

RBM10 is a well-known RNA binding protein that regulates alternative splicing in various disease states. We have shown a splicing-independent function of RBM10 that regulates heart failure. This study aims to unravel a new biological function of RBM10 phosphorylation by proto-oncogene cSrc that enables anti-hypertrophy gene program and controls cardiac hypertrophy.

MATERIALS AND METHODS

We employ in vitro and in vivo approaches to characterise RBM10 phosphorylation at three-tyrosine residues (Y81, Y500, and Y971) by cSrc and target mRNA regulation. We also use isoproterenol induced rat heart and cellular hypertrophy model to determine role of cSrc-mediated RBM10 phosphorylation.

KEY FINDINGS

We show that RBM10 phosphorylation is induced in cellular and animal heart model of cardiac hypertrophy and regulates target mRNA expression and 3'-end formation. Inhibition of cSrc kinase or mutation of the three-tyrosine phosphorylation sites to phenylalanine accentuates myocyte hypertrophy, and results in advancement and an early attainment of hypertrophy in the heart. RBM10 is down regulated in the hypertrophic myocyte and that its re-expression reverses cellular and molecular changes in the myocyte. However, in the absence of phosphorylation (cSrc inhibition or phospho-deficient mutation), restoration of endogenous RBM10 level in the hypertrophic heart or ectopic re-expression in vitro failed to reverse cardiomyocyte hypertrophy. Mechanistically, loss of RBM10 phosphorylation inhibits nuclear localisation and interaction with Star-PAP compromising anti-hypertrophy gene expression.

SIGNIFICANCE

Our study establishes that cSrc-mediated RBM10 phosphorylation arbitrates anti-hypertrophy gene program. We also report a new functional regulation of RBM10 by phosphorylation that is poised to control heart failure.

Municipal solid waste generation and its compositional assessment for efficient and sustainable infrastructure planning in an intermediate city of Pakistan

It is imperative to design and operate sustainable solid waste management (SWM) systems in cities based on the results of waste amount and characterization study (WACS). In this work, WACS was conducted and results were used to design an SWM system for an intermediate city of Pakistan. The study revealed that about 110 tons of solid waste per day is generated with a per capita rate of 0.337 kg/day. Around 51.2% of mixed municipal solid waste (MSW) is organic in nature and its non-scientific disposal is resulting in higher greenhouse gas (GHG) emissions. It was also found that more than 80% of valuables are taken away by the informal sector during the transfer of MSW from the generation source to the dumping site. Ultimate analyses showed that the moisture content (MC) and carbon to nitrogen (C:N) ratio were 64.23% and 51.14%, respectively. Proximate analysis revealed that moisture and calorific values were 57 % and 3505 BTU/lb., respectively. Based on these results, a material sorting facility (MSF) was proposed, with an estimated investment cost of US $3.64 million. However, the efficiency of the existing collection system is limited to 32 % only. In order to improve the collection efficiency (>90 %), an additional investment of US $1.638 million was estimated with an operations and maintenance (O&M) cost of US $19.25 per ton. Existing non-scientific MSW disposal practices contribute 32,079.61 CO2e tons/year of GHG emissions. The proposed MSF followed by composting is estimated to reduce GHG emissions by 38% to 19,722.38 CO2e tons/year.

Anti-oxidant and anti-inflammatory effects of cinnamaldehyde and eugenol on mononuclear cells of rheumatoid arthritis patients

Rheumatoid arthritis (RA) is an autoimmune disorder affecting joints and frequently characterized by initial local and later systemic inflammation. The present study was conducted with the aim to determine the anti-inflammatory and antioxidant effects of cinnamaldehyde and eugenol in the peripheral blood mononuclear cells (PBMC) of RA patients. PBMCs obtained from RA patients were treated with varying concentrations of cinnamaldehyde and eugenol. The levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were monitored in the 24-h culture supernatant of PBMCs. Reactive oxygen species formation, biomolecular oxidation and the activities of antioxidant enzymes were also determined. FTIR analysis was done to determine structural alterations in the PBMCs. Molecular docking was performed to gain an insight into the binding mechanism of eugenol and cinnamaldehyde with pro-inflammatory cytokines. The levels of pro-inflammatory cytokines and markers of oxidative stress were found to be elevated in the PBMC culture of RA patients as compared to the healthy controls. Cinnamaldehyde and eugenol have significantly reduced the levels of cytokines. Reactive oxygen species formation, biomolecular oxidation and antioxidant defense response were also ameliorated by treating PBMCs with both the compounds. FTIR results further confirms cinnamaldehyde and eugenol mediated protection to biomolecules of PBMCs of RA patients. Molecular docking results indicates interaction of cinnamaldehyde and eugenol with key residues of TNF-α and IL-6. Cinnamaldehyde and eugenol were found to exert potent anti-inflammatory and anti-oxidant effects on the PBMC culture of RA patients. So, these compounds may be used as an adjunct in the management of RA.

Syringic acid protects from isoproterenol induced cardiotoxicity in rats

Identification of pharmacologically potent antioxidant compounds for their use in preventive medicine is thrust area of current research. This study was undertaken with the aim of determining the protective role of syringic acid (SA) on isoproterenol (ISO) induced myocardial infarction (MI) in rats. SA was orally given to rats for 21 days at three different concentrations (12.5, 25 and 50 mg/kg). At 20th and 21st day, rats were subcutaneously injected with ISO and at the end of experimental period, rats were killed. ISO induced myocardial damage was averted by pre-co-treatment of SA, as decrease was found in serum level of marker enzymes (CKMB, LDH, AST, ALT), lipid peroxidation, protein carbonyl (PC) and proinflammatory cytokines (TNFα, IL 6). Furthermore, content of glutathione (GSH) and activities of antioxidant enzymes in heart tissue were significantly raised. Improvement in infarct size and erythrocyte (RBCs) morphology was also observed. The biochemical findings were supported by histopathological outcome and protective effect of SA was found to be dose dependent. The results of our study demonstrated that the cardioprotective potential of SA in rat model of ISO induced MI might be due to anti-lipid peroxidative and endogenous antioxidant system enhancement effects.

Cinnamaldehyde and eugenol attenuates collagen induced arthritis via reduction of free radicals and pro-inflammatory cytokines

BACKGROUND

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease which leads to bone and cartilage erosion. Oxidative stress and pro-inflammatory cytokines plays crucial role in the pathophysiology of RA. Cinnamaldehyde and eugenol have a long history of medical use in various inflammatory disorders.

PURPOSE

The drugs available for the treatment of RA are associated with various side effects. The present study was conducted to evaluate the anti-arthritic effects of cinnamaldehyde and eugenol in rat model of arthritis.

METHODS

Type II collagen was intradermally injected to rats for the induction of arthritis. Cinnamaldehyde (10 and 20 mg/kg/day) and eugenol (10 and 20 mg/kg/day) were given orally for 15 days, starting from day 21 to 35. Dexamethasone treated rats served as positive control. Histological, radiological and scanning electron microscopic analysis were done to monitor the effect of compounds on collagen induced arthritis (CIA). Reactive oxygen species (ROS) formation, nitric oxide and antioxidant status were also determined. The markers of biomolecular oxidation (protein, lipid and DNA) and activities of enzymatic antioxidants (superoxide dismutase, glutathione peroxidase, catalase and glutathione reductase) were also evaluated in the joint homogenate and plasma of rats. For detecting inflammation, levels of TNF-α, IL-6 and IL-10 were monitored by ELISA.

RESULTS

Our results showed anti-oxidant and anti-inflammatory effects of cinnamaldehyde and eugenol in arthritic rats. Scanning electron microscopy, histopathological and radiological findings also confirmed the anti-arthritic effects of cinnamaldehyde and eugenol. Both the compounds were effective in bringing significant decrease in the levels of ROS, nitric oxide, markers of biomolecular oxidation and increase in enzymatic and non-enzymatic antioxidants. The levels of TNF-α, IL-6 and IL-10 were also ameliorated by cinnamaldehyde and eugenol treatment. Between the two phytochemicals used, eugenol was found to be more effective than cinnamaldehyde in reducing the severity of arthritis.

CONCLUSION

Cinnamaldehyde and eugenol were effective in ameliorating oxidative stress and inflammation in arthritic rats. These findings indicate that cinnamaldehdye and eugenol have a great potential to be used as an adjunct in the management of RA.

Role of hydrotherapy in the amelioration of oxidant-antioxidant status in rheumatoid arthritis patients

AIM

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease. Reactive oxygen species (ROS) are involved in the pathophysiology of RA. Moderate intensity exercises have been reported to have anti-oxidant and anti-inflammatory effects. The aim of this study was to evaluate the effect of hydrotherapy on oxidant-antioxidant status in RA patients.

METHODS

Forty RA patients and 30 age- and sex-matched healthy controls were included in this study. RA patients were subdivided into two groups: the first group (n = 20) received treatment with conventional RA drugs, while the second group (n = 20) received hydrotherapy along with the conventional drugs for a period of 12 weeks. Disease Activity Score of 28 joints (DAS-28), ROS level, protein oxidation, lipid peroxidation, DNA damage and the activities of antioxidant enzymes were evaluated before and after 12 weeks of treatment.

RESULTS

RA patients showed a significant change in the oxidative stress biomarkers (ROS, P < 0.01; ferric reducing antioxidant potential, P < 0.001; malondialdehyde, P < 0.01; protein carbonyl, P < 0.001; tail length, P < 0.05) and decrease in the activities of anti-oxidant enzymes (superoxide dismutase [SOD], P < 0.01; glutathione peroxidase [GPx], P < 0.001). Conventional drug treatment has not produced any significant change in these parameters. However, cotreatment of drugs with hydrotherapy has decreased protein, lipid and DNA oxidation by increasing the activities of antioxidant enzymes (SOD and GPx).

CONCLUSION

Our results indicate that hydrotherapy along with drugs has reduced the severity of disease (DAS-28) by ameliorating the oxidant-antioxidant status in RA patients. Thus, in addition to conventional drugs, RA patients should be advised to have hydrotherapy (moderate intensity exercise) in their treatment regimen.

Protective effect of syringaldehyde on biomolecular oxidation, inflammation and histopathological alterations in isoproterenol induced cardiotoxicity in rats

BACKGROUND

Ischemic injury during myocardial infarction (MI) is responsible for increased deaths among patients with cardiovascular disorders. Recently, research has been directed for finding treatment using natural compounds. This study was performed to investigate the effects of syrigaldehyde (SYD), a phytochemical against isoproterenol (ISO) induced cardiotoxicity model.

METHODS

For induction of MI, rats were intoxicated with two doses of ISO and were treated with SYD at three different concentrations (12.5, 25 & 50 mg/kg) both prior and simultaneous to ISO administration.

RESULTS

ISO group revealed amplified activity of marker enzymes (CKMB, LDH, AST, ALT), increased oxidation of proteins and lipid molecules. Moreover, augmentation in pro-inflammatory markers was also found. The same group also displayed marked changes in histopathology and erythrocyte (RBCs) morphology. SYD treated groups showed diminished levels of serum markers enzymes, lipid peroxidation and protein carbonyl (PC) with increment in antioxidant defense in cardiac tissues of ISO administered rats. Our findings also revealed the modulatory effect of SYD on membrane bound ATPases, showing that SYD significantly improved the ISO induced changes in membrane fluidity. Furthermore, decline in infarct size, alleviation of structural RBC damage and improved myocardial histopathological outcome were observed in treated groups. In addition, mitigation of biochemical and histopathological changes by SYD was found to be dependent on its concentration.

CONCLUSION

SYD had cardioprotective efficacy owing to its antioxidative and anti-inflammatory properties. Our results support incorporation of SYD in regular diet for prevention of MI.

Elevated DNA Damage, Oxidative Stress, and Impaired Response Defense System Inflicted in Patients With Myocardial Infarction

BACKGROUND

Ischemic tissue damage in myocardial infarction (MI) is allied with the exaggerated production of reactive oxygen species (ROS) beyond the countering capability of chain-breaking radical scavengers, fallouts in the form of oxidatively burdened myocardial tissue.

METHODS

One hundred and twenty five patients with MI were included in the study to evaluate the dynamics of redox status of patients by monitoring the antioxidant potential, biomarkers of oxidative stress, lipid indices, RBC membrane damage when compared to healthy individuals in patients with MI congregated on the basis of Global Registry of Acute Coronary Events (GRACE) score, risk factors, and age.

RESULTS

Higher levels of malondialdehyde, 8-hydroxy-2-deoxyguanosine, lipid indices, ROS content, and membrane deterioration in erythrocytes were seen in patients with MI. Furthermore, reduced activities of erythrocyte antioxidant enzymes and lower concentrations of antioxidant molecules, plus reduced total antioxidant capacity, were observed in plasma of all patients with MI with respect to control. However, elevation in oxidative stress was found to be significantly marked in patients having GRACE score >100, risk factors, and MI >45 years when compared to patients with GRACE score ≤100, without risk factors, and MI ≤45 years, respectively.

CONCLUSION

These findings indicate the existence of increased oxidative damage and reduced antioxidant potential in patients with MI have a potent relationship with their GRACE risk score, risk factors, and age.

Level of inflammatory cytokines in rheumatoid arthritis patients: Correlation with 25-hydroxy vitamin D and reactive oxygen species

Background

Rheumatoid arthritis (RA) is an autoimmune inflammatory disorder. Reactive oxygen species (ROS) and pro-inflammatory cytokines have been believed to be involved in the etiopathogenesis of the disease. The aim of the study was to determine the correlation of inflammatory cytokines with 25-hydroxy vitamin D and ROS.

Methods

100 RA patients and 50 healthy age and sex matched individuals were included in the study. Patients were further divided on the basis of presence or absence of rheumatoid factor and disease severity. Serum 25-hydroxy vitamin D levels were monitored by chemiluminescent immunoassay. 10% hematocrit was used to detect the level of ROS by spectro fluorometer. The levels of inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-10 and IL-17) were determined in plasma by ELISA.

Results

The level of 25-hydroxy vitamin D was found to be decreased in RA patients in comparison to the control group. However the level of ROS and inflammatory cytokines were found to be elevated in RA patients in comparison with the healthy controls, with the increase being more pronounced in seropositive and RA patients having high disease severity. Inflammatory cytokines showed negative correlation with 25-hydroxy vitamin D and positive correlation with ROS.

Conclusion

This study for the first time shows the association of inflammatory cytokines with 25-hydroxy vitamin D and ROS in RA patients. The results suggest that 25-hydroxy vitamin D being an immune modulator is decreased in the serum of RA patients. Further ROS and cytokines play an important role in the pathogenesis of RA and are responsible for increasing the severity of disease.

A novel homozygous mutation disrupting the initiation codon in the SLURP1 gene underlies mal de Meleda in a consanguineous family

Mal de Meleda (MDM) is a palmoplantar keratoderma (PPK), characterized by hyperkeratosis of the palms and soles, and keratotic skin lesions. Patients with MDM can develop perioral erythema, keratotic and lichenoid plaques over the joints (including the elbows and knees), nail abnormalities, joint contractures and stiffness, brachydactyly, sclerodactyly, pseudoainhum, and malodorous maceration. MDM is associated with mutations in the SLURP1 gene. We report a consanguineous family in which MDM was inherited in an autosomal recessive manner. Genotyping using microsatellite markers established linkage in the family to the SLURP1 gene, which has been mapped previously to chromosome 8q24.3. Sequence analysis revealed a homozygous missense mutation (c.2T>C, p.Met1Thr) in affected family members. Molecular docking studies using a ZDOCK server predicted disruption of binding of the mutant variant to its target α7-nAChR. This study further supports the previously reported findings that homozygous mutations in the SLURP1 gene cause MDM.

Genetic variants in the tumor Necrosis Factor-Related Apoptosis-Inducing Ligand (TRAIL) do not contribute but Death Receptor (DR4) genes may contribute to susceptibility to head and neck cancer in Pakistani population

TRAIL mediated signaling in cancer cells has emerged as one amongst the most deeply studied molecular phenomenon. Recent breakthroughs have shown that overexpression of anti-apoptotic proteins, inactivation of pro-apoptotic proteins, transcriptional downregulation of TRAIL, DR4/DR5, degradation of DR/DR5 are some of the mechanisms which dramatically abrogate TRAIL induced apoptosis in cancer cells. Data obtained through genetic studies has highlighted highly polymorphic nature of DR4 and in accordance with this concept, we investigated the association between Head and Neck Cancer and polymorphisms in TRAIL (1595 C/T) and DR4 (C626G and A1322G) gene. We selected 100 patients with Head and Neck Cancer and 100 healthy, sex and age matched volunteers randomly. C626G and A1322G in DR4 gene were analyzed using Polymerase Change Reaction (PCR) - Restriction Fragment Length Polymorphism (RFLP) and Amplification Refractory Mutation System (ARMS) techniques respectively. For TRAIL gene 1595 C>T genotypes, there was no statistically significant role of homozygous CC or TT in Head and Neck cancer. CC was 58% in patients and 49% in controls. CT was 30% in patients and 43% in controls. TT was 12% in patients and 8% in controls. Allele frequency for C was noted to be 0.73 (patients) and 0.705 (controls), p-value (1). For T, 0.025 (patients) and 0.001(controls), p-value (0.88). The genotyping for DR4 gene 626 C>G polymorphism was done for 100 head and neck cancer patients and 100 age and sex matched healthy controls. All the genotypes for the polymorphism were in Hardy-Weinberg Equilibrium. For DR4626 C>G genotype, CC was 10% in patients and 2% in controls. GC was 63% in patients and 40% in controls. GG was 27% in patients and 58% in controls. Interestingly, in DR4 genotyping, CC was predisposing factor and GG acted as a protective factor. Allele frequency for C was noted to be 0.41 (patients) and 0.22 (controls), p-value (0.81). For G, 0.585 (patients) and 0.78 (controls), p-value (0.867). For the A1322G polymorphism, TT was 23% in patients and 36% in controls with a p-value 0.09 (table 6). CT was statistically significant in patients (45%) and controls (28%), p-value 0.04. CC was non-significant in patients (32%) and controls (36%), p-value 0.62 (table 6). C allele was 0.45% in patients and 0.5% in controls. T allele was 0.54% in patients and 0.5% in controls. Future studies must converge on somatic mutations, epigenetic mutations and expression analysis of TRAIL and DR4 to get a step closer to individualized medicine.

Phytopythium: molecular phylogeny and systematics

The genus Phytopythium (Peronosporales) has been described, but a complete circumscription has not yet been presented. In the present paper we provide molecular-based evidence that members of Pythium clade K as described by Lévesque & de Cock (2004) belong to Phytopythium. Maximum likelihood and Bayesian phylogenetic analysis of the nuclear ribosomal DNA (LSU and SSU) and mitochondrial DNA cytochrome oxidase subunit 1 (COI) as well as statistical analyses of pairwise distances strongly support the status of Phytopythium as a separate phylogenetic entity. Phytopythium is morphologically intermediate between the genera Phytophthora and Pythium. It is unique in having papillate, internally proliferating sporangia and cylindrical or lobate antheridia. The formal transfer of clade K species to Phytopythium and a comparison with morphologically similar species of the genera Pythium and Phytophthora is presented. A new species is described, Phytopythium mirpurense.