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Fulltext Does military spending stifle economic growth? The empirical evidence from non-OECD countries

Azam M

Heliyon, 2020 Dec;6(12):e05853.
PMID: 33426342 DOI: 10.1016/j.heliyon.2020.e05853

Undeniably, peace and long-term sustainable economic development are the prime agenda of all countries. This study aims to empirically evaluate the impact of military spending on economic growth for a panel of 35 non-OECD countries over 1988-2019. A multivariate regression model based on the augmented production function is used to achieve the objective of the study. The panel autoregressive distributed lag (ARDL)/pooled mean group (PMG) technique is employed, while, in addition the robust least squares and fixed-effect estimators are implemented for the robustness of the results. This study found a clear negative effect of military spending on economic growth. The pairwise Dumitrescu Hurlin panel causality test results exhibit bi-directional causality between military expenses and economic growth. Overall, these estimates provide strong support that military expenditure is not beneficial rather detrimental to economic growth. The empirical findings of this study suggest that policymakers need to redesign the military budget to stimulate economic growth and improve social welfare.
Growth-corruption-health triaca and environmental degradation: empirical evidence from Indonesia, Malaysia, and Thailand

Azam M, Khan AQ

Environ Sci Pollut Res Int, 2017 Jul;24(19):16407-16417.
PMID: 28550635 DOI: 10.1007/s11356-017-9299-4

This study examines the impact of economic growth, corruption, health, and poverty on environmental degradation for three countries from ASEAN, namely Indonesia, Malaysia, and Thailand using annual data over the period of 1994-2014. The relationship between environmental degradation (pollution) by carbon dioxide (CO2) emissions and economic growth is examined along with some other variables, namely health expenditure, poverty, agriculture value added growth, industrial value added growth, and corruption. The ordinary least squares (OLS) method is applied as an analytical technique for parameter estimation. The empirical results reveal that almost all variables are statistically significant at the 5% level of significance, whereby test rejects the null hypotheses of non-cointegration, indicating that all variables play an important role in affecting the environment across countries. Empirical results also indicate that economic growth has significant positive impact, while health expenditures show significantly negative impact on the environment. Corruption has significant positive effect on environment in the case of Malaysia; while in the case of Indonesia and Thailand, it has insignificant results. However, for the individual analysis across countries, the regression estimate suggests that economic growth has a significant positive relationship with environment for Indonesia, while it is found insignificantly negative and positive in the case of Malaysia and Thailand, respectively, during the period under the study. Empirical findings of the study suggest that policy-makers require to make technological-friendly environment sequentially to surmount unregulated pollution, steady population transfers from rural areas to urban areas are also important, and poverty alleviation and better health provision can also help to improve the environment.
Does foreign direct investment limit trade-adjusted carbon emissions: fresh evidence from global data

Azam M, Raza A

Environ Sci Pollut Res Int, 2022 Jan 24.
PMID: 35067883 DOI: 10.1007/s11356-021-18088-9

Environmental degradation has been a major concern for nations globally in recent years as carbon emissions have increased. Environmental degradation, if not controlled, is one of the dangers faced by humankind, and achieving sustainable development goals is not possible without improving environmental quality. Thus, reliable carbon emission measurement plays an important role in developing an effective climate strategy to address the current environmental issues. Following the trade-adjusted carbon emission measure, an effective climate strategy can be formulated especially following the 17 United Nation Sustainable Development Goals that are intended to lead to improvements toward a sustainable future. To fill the gap in the literature, we empirically explore the interrelationship between foreign capital flows and environmental quality measured by trade-adjusted consumption-based carbon dioxide (CCO2) emissions for a panel of 125 countries in 1990-2018 by revisiting the pollution haven hypothesis (PHH). The results obtained using system GMM analysis show that FDI has a significantly positive link with CCO2 in Asia and Africa, but the links between these two variables are insignificant in the Latin American, Caribbean, and European regions. In the cases of the full-sample and developing countries, a significantly positive relationship is found between FDI and CCO2. In the case of income-based samples, results reveal that FDI is the cause of environmental degradation in low-income, lower-middle-income, and upper-middle-income countries. These findings suggest that developing countries should adopt environmentally friendly policies to attract foreign investors by setting strict regulations on environmental pollution control to achieve sustainable development goals (SDGs).
Case report: robotic thoracic surgery of posterior mediastinal mass

Adli Azam MR, Shahril K, Aneez Ahmed DB

Med J Malaysia, 2020 07;75(4):428-429.
PMID: 32724008

We report a 39-year-old male with accidental findings of posterior mediastinum mass at right superior aspects, located at T2 with close proximity to trachea, superior vena cava, azygus vein, right subclavian artery and oesophagus. Apart from intermittent right shoulder pain, there was no other significant symptom. He opted for conservative management initially, given the benign nature and proximity to important structures. We postulated that robotic approach will be of advantage for this particular case which was successfully performed with uneventful recovery. This case illustrated the advantages of robotic-assisted surgery, compared to conventional VATS in otherwise potentially difficult case to undertake.
The dynamic relationship between structural change and CO2 emissions in Malaysia: a cointegrating approach

Ali W, Abdullah A, Azam M

Environ Sci Pollut Res Int, 2017 May;24(14):12723-12739.
PMID: 28378312 DOI: 10.1007/s11356-017-8888-6

The current study investigates the dynamic relationship between structural changes, real GDP per capita, energy consumption, trade openness, population density, and carbon dioxide (CO2) emissions within the EKC framework over a period 1971-2013. The study used the autoregressive distributed lagged (ARDL) approach to investigate the long-run relationship between the selected variables. The study also employed the dynamic ordinary least squared (DOLS) technique to obtain the robust long-run estimates. Moreover, the causal relationship between the variables is explored using the VECM Granger causality test. Empirical results reveal a negative relationship between structural change and CO2 emissions in the long run. The results indicate a positive relationship between energy consumption, trade openness, and CO2 emissions. The study applied the turning point formula of Itkonen (2012) rather than the conventional formula of the turning point. The empirical estimates of the study do not support the presence of the EKC relationship between income and CO2 emissions. The Granger causality test indicates the presence of long-run bidirectional causality between energy consumption, structural change, and CO2 emissions in the long run. Economic growth, openness to trade, and population density unidirectionally cause CO2 emissions. These results suggest that the government should focus more on information-based services rather than energy-intensive manufacturing activities. The feedback relationship between energy consumption and CO2 emissions suggests that there is an ominous need to refurbish the energy-related policy reforms to ensure the installations of some energy-efficient modern technologies.
Environment and air pollution like gun and bullet for low-income countries: war for better health and wealth

Zou X, Azam M, Islam T, Zaman K

Environ Sci Pollut Res Int, 2016 Feb;23(4):3641-57.
PMID: 26493298 DOI: 10.1007/s11356-015-5591-3

The objective of the study is to examine the impact of environmental indicators and air pollution on "health" and "wealth" for the low-income countries. The study used a number of promising variables including arable land, fossil fuel energy consumption, population density, and carbon dioxide emissions that simultaneously affect the health (i.e., health expenditures per capita) and wealth (i.e., GDP per capita) of the low-income countries. The general representation for low-income countries has shown by aggregate data that consist of 39 observations from the period of 1975-2013. The study decomposes the data set from different econometric tests for managing robust inferences. The study uses temporal forecasting for the health and wealth model by a vector error correction model (VECM) and an innovation accounting technique. The results show that environment and air pollution is the menace for low-income countries' health and wealth. Among environmental indicators, arable land has the largest variance to affect health and wealth for the next 10-year period, while air pollution exerts the least contribution to change health and wealth of low-income countries. These results indicate the prevalence of war situation, where environment and air pollution become visible like "gun" and "bullet" for low-income countries. There are required sound and effective macroeconomic policies to combat with the environmental evils that affect the health and wealth of the low-income countries.
Are globalization, urbanization, and energy consumption cause carbon emissions in SAARC region? New evidence from CS-ARDL approach

Azam M, Uddin I, Khan S, Tariq M

Environ Sci Pollut Res Int, 2022 Dec;29(58):87746-87763.
PMID: 35821313 DOI: 10.1007/s11356-022-21835-1

This study examines the impact of energy consumption, urbanization, and globalization on environmental degradation proxied by carbon emissions (CO2) in the South Asian Association for Regional Cooperation (SAARC) countries, namely Sri Lanka, Pakistan, Maldives, Nepal, Bhutan, Bangladesh, and India using data over the period 1990-2018. The cross-sectional autoregressive distributed lag (CS-ARDL), pooled mean group (PMG), and Dumitrescu and Hurlin (D-H) Granger causality techniques are employed for the empirical analysis. First and second-generation panel unit root tests are used to determine the stationary level of all data series which reveals mixed order of integration. The empirical findings show that urbanization, gross domestic product (GDP) per capita income, energy consumption, industrial growth, globalization, and financial development cause CO2 emissions, while the other variables, namely arable land and innovation, put negative effects on CO2 emissions. Moreover, the D-H heterogeneous test results exhibit that bi-directional relationship exists between CO2 and arable land, urbanization, industrial growth, and financial development, while a unidirectional causality exists between CO2 emissions and GDP per head income. These findings suggest that planned urbanization, investment in renewable energy sources, and effective strategies regarding the economic and financial integration with the global economies are required for a clean and green environment.
Do demographic factors affect the environment? Empirical evidence from the Middle East and North African countries

Haouas I, Haseeb M, Azam M, Rehman ZU

Environ Sci Pollut Res Int, 2023 Jul;30(31):77077-77095.
PMID: 37249784 DOI: 10.1007/s11356-023-27835-z

Every country intends to enhance national production by achieving sustainable development. The purpose of this study is to examine whether there exists any long-run association among environmental deterioration measured by territorial emissions in CO2, demographic factors (total population, population density, and urban population) and some other variables, namely, energy use, per capita income, energy intensity, and industrial value added for the 16 countries from the Middle East and North African (MENA) over 1990-2018. We implemented the generalized method of moments (GMM), fully modified ordinary least square (FMOLS), robust least square estimators, and panel Granger causality techniques for estimation. The empirical estimates reveal that there exists a long run cointegration among the series. Results also exhibit that energy use, per capita income, energy intensity, industrial value added, population density, total population, and urban population have positive effects on CO2 emissions. Furthermore, in each panel, there is bi-directional causality between population density and CO2 emissions, total population and CO2 emissions, and urban population and CO2 emissions. These findings suggest that the policymakers need not exclusively to focus on the transformation of rural labor from an agricultural-based model to urban regions with powerful, dominant industry and services sectors but also related to the changing of rural establishments into urban spaces is required. These changes in demographics involve changes in the demand for additional transportation services, food, shelter, clothing, and other necessities.
Complete resolution of constrictive pericarditis after coronary bypass surgery

Paneer SKM, Christina SR, Adli Azam MR, Balachandran K, Deventhiran P

Med J Malaysia, 2021 Sep;76(5):747-749.
PMID: 34508388

Classical constrictive pericarditis (CP) is an unusual and rare complication after coronary artery bypass grafting. It can be transient, progressive or fixed form of cardiac constriction. However recently recognized transient variant of constrictive pericarditis can be managed with medical therapy, though other progressive and irreversible forms may require pericardiectomy. We describe a 65-year-old male patient who developed a classical but a very early transient CP, just within two weeks as a result of post cardiac injury syndrome after coronary bypass surgery. The patient had a complete recovery following medical treatment.
Fulltext Thigh Pain and Peri-Implant Fractures with the Use of Short Cephalo-medullary Nails: A Retrospective Study of 122 Patients

Dubey S, Iyer RD, Azam MQ, Sarkar B, Nongdamba H

Malays Orthop J, 2022 Nov;16(3):17-23.
PMID: 36589363 DOI: 10.5704/MOJ.2211.004

INTRODUCTION: To assess the incidence and causes of persistent thigh pain and peri-implant fractures after union in patients of intertrochanteric fractures treated with short cephalo-medullary nails.
MATERIALS AND METHODS: A retrospective observational study conducted at a Level 1 Trauma centre. A total of 122 patients of intertrochanteric fractures who were operated using short cephalo-medullary nails (170mm and 200mm lengths) between January 2018 to June 2019 were included in the study. Main outcomes measured were the incidence of thigh pain and peri-implant fractures.
RESULTS: Out of the 122 patients with a mean follow-up of 14.1 month, 12 patients had persistent thigh pain. Six patients had the helical blade protruding from the lateral cortex, two of them had distal tip of nail abutting on the anterior cortex and four cases had prominent proximal segment of nail which may explain the cause of their pain. Five of these patients had a combination of these findings. Two patients had pain for which no other obvious cause was found. There were no cases of peri-implant fractures in our study.
CONCLUSION: Thigh pain associated with the use of short cephalon-medullary nails is often unrelated to nail length and can be prevented by using proper surgical technique. There seems to be no association between the use of short nails and peri-implant fractures.
The impact of CO2 emissions on economic growth: evidence from selected higher CO2 emissions economies

Azam M, Khan AQ, Bin Abdullah H, Qureshi ME

Environ Sci Pollut Res Int, 2016 Apr;23(7):6376-89.
PMID: 26620862 DOI: 10.1007/s11356-015-5817-4

The main purpose of this work is to analyze the impact of environmental degradation proxied by CO2 emissions per capita along with some other explanatory variables namely energy use, trade, and human capital on economic growth in selected higher CO2 emissions economies namely China, the USA, India, and Japan. For empirical analysis, annual data over the period spanning between 1971 and 2013 are used. After using relevant and suitable tests for checking data properties, the panel fully modified ordinary least squares (FMOLS) method is employed as an analytical technique for parameter estimation. The panel group FMOLS results reveal that almost all variables are statistically significant, whereby test rejects the null hypotheses of non cointegration, demonstrating that all variables play an important role in affecting the economic growth role across countries. Where two regressors namely CO2 emissions and energy use show significantly negative impacts on economic growth, for trade and human capital, they tend to show the significantly positive impact on economic growth. However, for the individual analysis across countries, the panel estimate suggests that CO2 emissions have a significant positive relationship with economic growth for China, Japan, and the USA, while it is found significantly negative in case of India. The empirical findings of the study suggest that appropriate and prudent policies are required in order to control pollution emerging from areas other than liquefied fuel consumption. The ultimate impact of shrinking pollution will help in supporting sustainable economic growth and maturation as well as largely improve society welfare.
Causal nexus between energy consumption and carbon dioxide emission for Malaysia using maximum entropy bootstrap approach

Gul S, Zou X, Hassan CH, Azam M, Zaman K

Environ Sci Pollut Res Int, 2015 Dec;22(24):19773-85.
PMID: 26282441 DOI: 10.1007/s11356-015-5185-0

This study investigates the relationship between energy consumption and carbon dioxide emission in the causal framework, as the direction of causality remains has a significant policy implication for developed and developing countries. The study employed maximum entropy bootstrap (Meboot) approach to examine the causal nexus between energy consumption and carbon dioxide emission using bivariate as well as multivariate framework for Malaysia, over a period of 1975-2013. This is a unified approach without requiring the use of conventional techniques based on asymptotical theory such as testing for possible unit root and cointegration. In addition, it can be applied in the presence of non-stationary of any type including structural breaks without any type of data transformation to achieve stationary. Thus, it provides more reliable and robust inferences which are insensitive to time span as well as lag length used. The empirical results show that there is a unidirectional causality running from energy consumption to carbon emission both in the bivariate model and multivariate framework, while controlling for broad money supply and population density. The results indicate that Malaysia is an energy-dependent country and hence energy is stimulus to carbon emissions.
Does globalization and financial sector development affect environmental quality? A panel data investigation for the Middle East and North African countries

Awan AM, Azam M, Saeed IU, Bakhtyar B

Environ Sci Pollut Res Int, 2020 Dec;27(36):45405-45418.
PMID: 32789804 DOI: 10.1007/s11356-020-10445-4

The broad purpose of this study is to empirically explore the impact of globalization and financial development on environmental pollution by carbon (CO2) emissions in the six Middle East and North Africa (MENA) countries using balanced panel data from 1971 to 2015. We also aimed to test the legitimacy of the environmental Kuznets curve (EKC) hypothesis for this region. The fixed-effects approach preferred by the Hausman specification test is used to estimate the empirical model, and the feasible generalized least squares (F.G.L.S.) estimator is employed to cope with any issue of heteroscedasticity and serial correlation. This study found that globalization and financial development have adverse and significant effects on environmental degradation and affirm the legitimacy of the EKC hypothesis for these countries. The finding of this study suggests that the governments of MENA countries should design and implement appropriate policies for strengthening the renewable sources of energy like wind, solar, bio-fuel, and thermal to decrease CO2 emissions and boost sustainable economic development. The policymakers should focus on the efficiency of institutions and enhancement of energy-saving projects in this region.
The impact of geopolitical risk, institutional governance and green finance on attaining net-zero carbon emission

Hunjra AI, Azam M, Verhoeven P, Taskin D, Dai J

J Environ Manage, 2024 May 06;359:120927.
PMID: 38714030 DOI: 10.1016/j.jenvman.2024.120927

This research investigates the impact of geopolitical risk, institutional governance and green finance on environmental outcomes, specifically focusing on carbon emissions and ecological footprint. Utilizing the dynamic CS-ARDL method and aggregated mean group analysis on a panel dataset covering 21 nations from 2000 to 2021, our findings reveal that heightened geopolitical risk leads to both short and long run increases in carbon emissions and the ecological footprint. Our study finds both a direct as well as indirect connection between governance, green finance and environmental outcomes in both the short and long run, highlighting the nuanced impact of governance on the formulation of environmental policies and regulatory frameworks. The results emphasize the need for targeted strategies, including focused investments and incentives for sustainable finance, particularly in conflict-affected regions. Furthermore, our research underscores the enduring impact of historical events, such as wars, on contemporary environmental indicators, emphasizing the importance of proactive conflict prevention measures. Our research suggests that policymakers should adopt comprehensive strategies that prioritize emission reduction during short-run spikes in geopolitical risk while maintaining a steadfast commitment to long-run sustainability.
Transtibial prosthetic socket pistoning: static evaluation of Seal-In(®) X5 and Dermo(®) Liner using motion analysis system

Gholizadeh H, Osman NA, Kamyab M, Eshraghi A, Abas WA, Azam MN

Clin Biomech (Bristol, Avon), 2012 Jan;27(1):34-9.
PMID: 21794965 DOI: 10.1016/j.clinbiomech.2011.07.004

The method of attachment of prosthesis to the residual limb (suspension) and socket fitting is a critical issue in the process of providing an amputee with prosthesis. Different suspension methods try to minimize the pistoning movement inside the socket. The Seal-In(®) X5 and Dermo(®) Liner by Ossur are new suspension liners that intend to reduce pistoning between the socket and liner. Since the effects of these new liners on suspension are unclear, the objective of this study was to compare the pistoning effect of Seal-In(®) X5 and Dermo(®) Liner by using Vicon Motion System.
Fulltext Improving Vesicular Integrity and Antioxidant Activity of Novel Mixed Soy Lecithin-Based Liposomes Containing Squalene and Their Stability against UV Light

Toopkanloo SP, Tan TB, Abas F, Azam M, Nehdi IA, Tan CP

Molecules, 2020 Dec 11;25(24).
PMID: 33322600 DOI: 10.3390/molecules25245873

In order to improve the membrane lipophilicity and the affinity towards the environment of lipid bilayers, squalene (SQ) could be conjugated to phospholipids in the formation of liposomes. The effect of membrane composition and concentrations on the degradation of liposomes prepared via the extrusion method was investigated. Liposomes were prepared using a mixture of SQ, cholesterol (CH) and Tween80 (TW80). Based on the optimal conditions, liposome batches were prepared in the absence and presence of SQ. Their physicochemical and stability behavior were evaluated as a function of liposome constituent. From the optimization study, the liposomal formulation containing 5% (w/w) mixed soy lecithin (ML), 0.5% (w/w) SQ, 0.3% (w/w) CH and 0.75% (w/w) TW80 had optimal physicochemical properties and displayed a unilamellar structure. Liposome prepared using the optimal formulation had a low particle size (158.31 ± 2.96 nm) and acceptable %increase in the particle size (15.09% ± 3.76%) and %trolox equivalent antioxidant capacity (%TEAC) loss (35.69% ± 0.72%) against UV light treatment (280-320 nm) for 6 h. The interesting outcome of this research was the association of naturally occurring substance SQ for size reduction without the extra input of energy or mechanical procedures, and improvement of vesicle stability and antioxidant activity of ML-based liposome. This study also demonstrated that the presence of SQ in the membrane might increase the acyl chain dynamics and decrease the viscosity of the dispersion, thereby limiting long-term stability of the liposome.
Fulltext Interaction between nitric oxide and renal α1-adrenoreceptors mediated vasoconstriction in rats with left ventricular hypertrophyin Wistar Kyoto rats

Ahmad A, Sattar MA, Azam M, Khan SA, Bhatt O, Johns EJ

PLoS One, 2018;13(2):e0189386.
PMID: 29447158 DOI: 10.1371/journal.pone.0189386

Left ventricular hypertrophy (LVH) is associated with decreased responsiveness of renal α1-adrenoreceptors subtypes to adrenergic agonists. Nitric oxide donors are known to have antihypertrophic effects however their impact on responsiveness of renal α1-adrenoreceptors subtypes is unknown. This study investigated the impact of nitric oxide (NO) and its potential interaction with the responsiveness of renal α1-adrenoreceptors subtypes to adrenergic stimulation in rats with left ventricular hypertrophy (LVH). This study also explored the impact of NO donor on CSE expression in normal and LVH kidney. LVH was induced using isoprenaline and caffeine in drinking water for 2 weeks while NO donor (L-arginine, 1.25g/Lin drinking water) was given for 5 weeks. Intrarenal noradrenaline, phenylephrine and methoxamine responses were determined in the absence and presence of selective α1-adrenoceptor antagonists, 5- methylurapidil (5-MeU), chloroethylclonidine (CeC) and BMY 7378. Renal cortical endothelial nitric oxide synthase mRNA was upregulated 7 fold while that of cystathione γ lyase was unaltered in the NO treated LVH rats (LVH-NO) group compared to LVH group. The responsiveness of renal α1A, α1B and α1D-adrenoceptors in the low dose and high dose phases of 5-MeU, CEC and BMY7378 to adrenergic agonists was increased along with cGMP in the kidney of LVH-NO group. These findings suggest that exogenous NO precursor up-regulated the renal eNOS/NO/cGMP pathway in LVH rats and resulted in augmented α1A, α1B and α1D adrenoreceptors responsiveness to the adrenergic agonists. There is a positive interaction between H2S and NO production in normal animals but this interaction appears absent in LVH animals.
Articular cartilage regeneration with autologous marrow aspirate and hyaluronic Acid: an experimental study in a goat model

Saw KY, Hussin P, Loke SC, Azam M, Chen HC, Tay YG, et al.

Arthroscopy, 2009 Dec;25(12):1391-400.
PMID: 19962065 DOI: 10.1016/j.arthro.2009.07.011

PURPOSE: The purpose of the study was to determine whether postoperative intra-articular injections of autologous marrow aspirate (MA) and hyaluronic acid (HA) after subchondral drilling resulted in better cartilage repair as assessed histologically by Gill scoring.
METHODS: In a goat model we created a 4-mm full-thickness articular cartilage defect in the stifle joint (equivalent to 1.6 cm in the human knee) and conducted subchondral drilling. The animals were divided into 3 groups: group A (control), no injections; group B (HA), weekly injection of 1 mL of sodium hyaluronate for 3 weeks; and group C (HA + MA), similar to group B but with 2 mL of autologous MA in addition to HA. MA was obtained by bone marrow aspiration, centrifuged, and divided into aliquots for cryopreservation. Fifteen animals were equally divided between the groups and sacrificed 24 weeks after surgery, when the joint was harvested, examined macroscopically and histologically.
RESULTS: Of the 15 animals, 2 from group A had died of non-surgery-related complications and 1 from group C was excluded because of a joint infection. In group A the repair constituted mainly scar tissue, whereas in group B there was less scar tissue, with small amounts of proteoglycan and type II collagen at the osteochondral junction. In contrast, repair cartilage from group C animals showed almost complete coverage of the defect with evidence of hyaline cartilage regeneration. Histology assessed by Gill scoring was significantly better in group C with 1-way analysis of variance yielding an F statistic of 10.611 with a P value of .004, which was highly significant.
CONCLUSIONS: Postoperative intra-articular injections of autologous MA in combination with HA after subchondral drilling resulted in better cartilage repair as assessed histologically by Gill scoring in a goat model.
CLINICAL RELEVANCE: After arthroscopic subchondral drilling, this novel technique may result in better articular cartilage regeneration.
Fulltext Cystathione gamma lyase/Hydrogen Sulphide Pathway Up Regulation Enhances the Responsiveness of α1A and α1B-Adrenoreceptors in the Kidney of Rats with Left Ventricular Hypertrophy

Ahmad A, Sattar MA, Azam M, Abdulla MH, Khan SA, Hashmi F, et al.

PLoS One, 2016;11(5):e0154995.
PMID: 27191852 DOI: 10.1371/journal.pone.0154995

The purpose of the present study was to investigate the interaction between H2S and NO (nitric oxide) in the kidney and to evaluate its impact on the functional contribution of α1A and α1B-adrenoreceptors subtypes mediating the renal vasoconstriction in the kidney of rats with left ventricular hypertrophy (LVH). In rats the LVH induction was by isoprenaline administration and caffeine in the drinking water together with intraperitoneal administration of H2S. The responsiveness of α1A and α1B to exogenous noradrenaline, phenylephrine and methoxaminein the absence and presence of 5-methylurapidil (5-MeU) and chloroethylclonidine (CEC) was studied. Cystathione gamma lyase (CSE), cystathione β synthase (CBS), 3-mercaptopyruvate sulphar transferase (3-MST) and endothelial nitric oxide synthase (eNOS) were quantified. There was significant up regulation of CSE and eNOS in the LVH-H2S compared to the LVH group (P<0.05). Baseline renal cortical blood perfusion (RCBP) was increased (P<0.05) in the LVH-H2S compared to the LVH group. The responsiveness of α1A-adrenergic receptors to adrenergic agonists was increased (P<0.05) after administration of low dose 5-Methylurapidil in the LVH-H2S group while α1B-adrenergic receptors responsiveness to adrenergic agonists were increased (P<0.05) by both low and high dose chloroethylclonidine in the LVH-H2S group. Treatment of LVH with H2S resulted in up-regulation of CSE/H2S, CBS, and 3-MST and eNOS/NO/cGMP pathways in the kidney. These up regulation of CSE/H2S, CBS, and 3-MST and eNOS/NO/cGMP pathways enhanced the responsiveness of α1A and α1B-adrenoreceptors subtypes to adrenergic agonists in LVH-H2S. These findings indicate an important role for H2S in modulating deranged signalling in the renal vasculature resulting from LVH development.
Effect of gasotransmitters treatment on expression of hypertension, vascular and cardiac remodeling and hypertensive nephropathy genes in left ventricular hypertrophy

Ahmad A, Riaz Z, Sattar MA, Khan SA, John EJ, Rashid S, et al.

Gene, 2020 May 05;737:144479.
PMID: 32068124 DOI: 10.1016/j.gene.2020.144479

BACKGROUND: Cardiac and renal dysfunction are often co-morbid pathologies leading to worsening prognosis resulting in difficulty in therapy of left ventricular hypertrophy (LVH). The aim of the current study was to determine the changes in expression of human ortholog genes of hypertension, vascular and cardiac remodeling and hypertensive nephropathy phenotypes under normal, disease and upon treatment with gasotransmitter including H2S (hydrogen sulphide), NO (nitric oxide) and combined (H2S + NO).
METHODS: A total of 72 Wistar Kyoto rats (with equivalent male and female animals) were recruited in the present study where LVH rat models were treated with H2S and NO individually as well as with both combined. Cardiac and renal physical indices were recorded and relative gene expression were quantified.
RESULTS: Both cardiac and renal physical indices were significantly modified with individual as well as combined H2S + NO treatment in control and LVH rats. Expression analysis revealed, hypertension, vascular remodeling genes ACE, TNFα and IGF1, mRNAs to be significantly higher (P ≤ 0.05) in the myocardia and renal tissues of LVH rats, while individual and combined H2S + NO treatment resulted in lowering the gene expression to normal/near to normal levels. The cardiac remodeling genes MYH7, TGFβ, SMAD4 and BRG1 expression were significantly up-regulated (P ≤ 0.05) in the myocardia of LVH where the combined H2S + NO treatment resulted in normal/near to normal expression more effectively as compared to individual treatments. In addition individual as well as combined H2S and NO treatment significantly decreased PKD1 expression in renal tissue, which was up-regulated in LVH rats (P ≤ 0.05).
CONCLUSIONS: The reduction in hemodynamic parameters and cardiac indices as well as alteration in gene expression on treatment of LVH rat model indicates important therapeutic potential of combined treatment with H2S + NO gasotransmitters in hypertension and cardiac hypertrophy when present as co-morbidity with renal complications.

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